Tweak serial output code

Marlin/src/HAL/HAL_STM32F7/TMC2660.cpp

 void TMC26XStepper::start() {
 
   #ifdef TMC_DEBUG1
-    SERIAL_ECHOPGM("\n  TMC26X stepper library  \n");
+    SERIAL_ECHOLNPGM("\n  TMC26X stepper library");
     SERIAL_ECHOPAIR("\n  CS pin: ", cs_pin);
     SERIAL_ECHOPAIR("\n  DIR pin: ", dir_pin);
     SERIAL_ECHOPAIR("\n  STEP pin: ", step_pin);

Marlin/src/feature/bedlevel/ubl/ubl.cpp

 
     SERIAL_ECHOPGM("\nBed Topography Report");
     if (human) {
-      SERIAL_ECHOPGM(":\n\n");
+      SERIAL_ECHOLNPGM(":\n");
       serial_echo_xy(4, MESH_MIN_X, MESH_MAX_Y);
       serial_echo_xy(twixt, MESH_MAX_X, MESH_MAX_Y);
       SERIAL_EOL();

Marlin/src/feature/bedlevel/ubl/ubl_G29.cpp

         #endif
 
         if (abort_flag) {
-          SERIAL_ECHOPGM("?Error probing point.  Aborting operation.\n");
+          SERIAL_ECHOLNPGM("?Error probing point.  Aborting operation.");
           return;
         }
       }

Marlin/src/feature/mixing.cpp

       SERIAL_ECHO_F(collector[i] / csum, 3);
       SERIAL_CHAR(' ');
     }
-    SERIAL_ECHOPGM("]\n");
+    SERIAL_ECHOLNPGM("]");
   #endif
 
   // Scale all values so their maximum is COLOR_A_MASK

Marlin/src/feature/pause.cpp

  */
 void resume_print(const float &slow_load_length/*=0*/, const float &fast_load_length/*=0*/, const float &purge_length/*=ADVANCED_PAUSE_PURGE_LENGTH*/, const int8_t max_beep_count/*=0*/ DXC_ARGS) {
   /*
-  SERIAL_ECHOPGM("start of resume_print()\n");
+  SERIAL_ECHOLNPGM("start of resume_print()");
   SERIAL_ECHOPAIR("\ndual_x_carriage_mode:", dual_x_carriage_mode);
   SERIAL_ECHOPAIR("\nextruder_duplication_enabled:", extruder_duplication_enabled);
   SERIAL_ECHOPAIR("\nactive_extruder:", active_extruder);
-  SERIAL_ECHOPGM("\n\n");
+  SERIAL_ECHOLNPGM("\n");
   //*/
 
   if (!did_pause_print) return;

Marlin/src/gcode/control/M605.cpp

 
       if (dual_x_carriage_mode == DXC_SCALED_DUPLICATION_MODE) {
         if (previous_mode != DXC_DUPLICATION_MODE) {
-          SERIAL_ECHOPGM("Printer must be in DXC_DUPLICATION_MODE prior to \n");
-          SERIAL_ECHOPGM("specifying DXC_SCALED_DUPLICATION_MODE.\n");
+          SERIAL_ECHOLNPGM("Printer must be in DXC_DUPLICATION_MODE prior to ");
+          SERIAL_ECHOLNPGM("specifying DXC_SCALED_DUPLICATION_MODE.");
           dual_x_carriage_mode = DEFAULT_DUAL_X_CARRIAGE_MODE;
           return;
         }

Marlin/src/gcode/parser.cpp

       SERIAL_ECHO(string_arg);
       SERIAL_CHAR('"');
     }
-    SERIAL_ECHOPGM("\n\n");
+    SERIAL_ECHOLNPGM("\n");
     for (char c = 'A'; c <= 'Z'; ++c) {
       if (seen(c)) {
         SERIAL_ECHOPAIR("Code '", c); SERIAL_ECHOPGM("':");
         }
         else
           SERIAL_ECHOPGM(" (no value)");
-        SERIAL_ECHOPGM("\n\n");
+        SERIAL_ECHOLNPGM("\n");
       }
     }
   }

Marlin/src/gcode/queue.cpp

   //SERIAL_ECHOPGM("\") \n");
 
   if (*cmd == 0 || *cmd == '\n' || *cmd == '\r') {
-    //SERIAL_ECHOPGM("Null command found...   Did not queue!\n");
+    //SERIAL_ECHOLNPGM("Null command found...   Did not queue!");
     return true;
   }
 

Marlin/src/module/configuration_store.cpp

         const bool status = persistentStore.write_data(pos, (uint8_t *)&ubl.z_values, sizeof(ubl.z_values), &crc);
         persistentStore.access_finish();
 
-        if (status) SERIAL_ECHOPGM("?Unable to save mesh data.\n");
+        if (status) SERIAL_ECHOLNPGM("?Unable to save mesh data.");
         else        CHITCHAT_ECHOLNPAIR("Mesh saved in slot ", slot);
 
       #else
         const uint16_t status = persistentStore.read_data(pos, dest, sizeof(ubl.z_values), &crc);
         persistentStore.access_finish();
 
-        if (status) SERIAL_ECHOPGM("?Unable to load mesh data.\n");
+        if (status) SERIAL_ECHOLNPGM("?Unable to load mesh data.");
         else        CHITCHAT_ECHOLNPAIR("Mesh loaded from slot ", slot);
 
         EEPROM_FINISH();

Marlin/src/module/endstops.cpp

       #if HAS_Z3_MAX
         ES_REPORT_CHANGE(Z3_MAX);
       #endif
-      SERIAL_ECHOPGM("\n\n");
+      SERIAL_ECHOLNPGM("\n");
       analogWrite(LED_PIN, local_LED_status);
       local_LED_status ^= 255;
       old_live_state_local = live_state_local;