Followup to recent patches

- `M666` is static, not inline
- Disambiguate some stepper macros

.travis.yml

   - pins_set RAMPS X_MAX_PIN -1
   - opt_add_adv Z2_MAX_PIN 2
   - build_marlin_pio ${TRAVIS_BUILD_DIR} ${TEST_PLATFORM}
-  
+
   #############################
   # DUE default config test
   #############################
-  
+
   - export TEST_PLATFORM="-e DUE"
   - restore_configs
   - opt_set MOTHERBOARD BOARD_RAMPS4DUE_EFB

Marlin/src/gcode/calibrate/M666.cpp

    * M666: Set Dual Endstops offsets for X, Y, and/or Z.
    *       With no parameters report current offsets.
    */
-  inline void GcodeSuite::M666() {
+  void GcodeSuite::M666() {
     bool report = true;
     #if ENABLED(X_DUAL_ENDSTOPS)
       if (parser.seen('X')) {

Marlin/src/gcode/temperature/M105.cpp

         port
       #endif
     );
-  #else // !HAS_TEMP_HOTEND && !HAS_TEMP_BED
+  #else // !HAS_TEMP_SENSOR
     SERIAL_ERROR_START_P(port);
     SERIAL_ERRORLNPGM_P(port, MSG_ERR_NO_THERMISTORS);
   #endif

Marlin/src/module/stepper.cpp

   #define LOCKED_X2_MOTOR locked_x2_motor
   #define LOCKED_Y2_MOTOR locked_y2_motor
   #define LOCKED_Z2_MOTOR locked_z2_motor
-  #define DUAL_ENDSTOP_APPLY_STEP(AXIS,v)                                                                                                             \
-    if (performing_homing) {                                                                                                                          \
-      if (AXIS##_HOME_DIR < 0) {                                                                                                                      \
-        if (!(TEST(endstops.old_endstop_bits, AXIS##_MIN) && (count_direction[AXIS##_AXIS] < 0)) && !LOCKED_##AXIS##_MOTOR) AXIS##_STEP_WRITE(v);     \
-        if (!(TEST(endstops.old_endstop_bits, AXIS##2_MIN) && (count_direction[AXIS##_AXIS] < 0)) && !LOCKED_##AXIS##2_MOTOR) AXIS##2_STEP_WRITE(v);  \
-      }                                                                                                                                               \
-      else {                                                                                                                                          \
-        if (!(TEST(endstops.old_endstop_bits, AXIS##_MAX) && (count_direction[AXIS##_AXIS] > 0)) && !LOCKED_##AXIS##_MOTOR) AXIS##_STEP_WRITE(v);     \
-        if (!(TEST(endstops.old_endstop_bits, AXIS##2_MAX) && (count_direction[AXIS##_AXIS] > 0)) && !LOCKED_##AXIS##2_MOTOR) AXIS##2_STEP_WRITE(v);  \
-      }                                                                                                                                               \
-    }                                                                                                                                                 \
-    else {                                                                                                                                            \
-      AXIS##_STEP_WRITE(v);                                                                                                                           \
-      AXIS##2_STEP_WRITE(v);                                                                                                                          \
+  #define DUAL_ENDSTOP_APPLY_STEP(AXIS,v)                                                                                                           \
+    if (performing_homing) {                                                                                                                        \
+      if (AXIS##_HOME_DIR < 0) {                                                                                                                    \
+        if (!(TEST(endstops.old_endstop_bits, AXIS##_MIN) && count_direction[AXIS##_AXIS] < 0) && !LOCKED_##AXIS##_MOTOR) AXIS##_STEP_WRITE(v);     \
+        if (!(TEST(endstops.old_endstop_bits, AXIS##2_MIN) && count_direction[AXIS##_AXIS] < 0) && !LOCKED_##AXIS##2_MOTOR) AXIS##2_STEP_WRITE(v);  \
+      }                                                                                                                                             \
+      else {                                                                                                                                        \
+        if (!(TEST(endstops.old_endstop_bits, AXIS##_MAX) && count_direction[AXIS##_AXIS] > 0) && !LOCKED_##AXIS##_MOTOR) AXIS##_STEP_WRITE(v);     \
+        if (!(TEST(endstops.old_endstop_bits, AXIS##2_MAX) && count_direction[AXIS##_AXIS] > 0) && !LOCKED_##AXIS##2_MOTOR) AXIS##2_STEP_WRITE(v);  \
+      }                                                                                                                                             \
+    }                                                                                                                                               \
+    else {                                                                                                                                          \
+      AXIS##_STEP_WRITE(v);                                                                                                                         \
+      AXIS##2_STEP_WRITE(v);                                                                                                                        \
     }
 #endif
 
   #define E_APPLY_STEP(v,Q) E_STEP_WRITE(v)
 #endif
 
-
-
 /**
  *         __________________________
  *        /|                        |\     _________________         ^
     // Advance the Bresenham counter; start a pulse if the axis needs a step
     #define PULSE_START(AXIS) do{ \
       _COUNTER(AXIS) += current_block->steps[_AXIS(AXIS)]; \
-      if (_COUNTER(AXIS) > 0) _APPLY_STEP(AXIS)(!_INVERT_STEP_PIN(AXIS), 0); }while(0)
+      if (_COUNTER(AXIS) > 0) { _APPLY_STEP(AXIS)(!_INVERT_STEP_PIN(AXIS), 0); } \
+    }while(0)
 
     // Advance the Bresenham counter; start a pulse if the axis needs a step
-    #define STEP_TICK(AXIS) \
+    #define STEP_TICK(AXIS) do { \
       if (_COUNTER(AXIS) > 0) { \
         _COUNTER(AXIS) -= current_block->step_event_count; \
-        count_position[_AXIS(AXIS)] += count_direction[_AXIS(AXIS)]; }
+        count_position[_AXIS(AXIS)] += count_direction[_AXIS(AXIS)]; \
+      } \
+    }while(0)
 
     // Stop an active pulse, if any
     #define PULSE_STOP(AXIS) _APPLY_STEP(AXIS)(_INVERT_STEP_PIN(AXIS), 0)