Add an option to specify "pulse" timer

Marlin/src/HAL/HAL_AVR/HAL_AVR.h

 #define STEPPER_TIMER_PRESCALE  8
 #define HAL_TICKS_PER_US        ((HAL_STEPPER_TIMER_RATE) / 1000000) // Cannot be of type double
 
+#define PULSE_TIMER_NUM         TEMP_TIMER_NUM
+#define TIMER_COUNTER_0         TCNT0
+#define PULSE_TIMER_PRESCALE    8
+
 #define ENABLE_STEPPER_DRIVER_INTERRUPT()  SBI(TIMSK1, OCIE1A)
 #define DISABLE_STEPPER_DRIVER_INTERRUPT() CBI(TIMSK1, OCIE1A)
 

Marlin/src/HAL/HAL_DUE/HAL_timers_Due.h

 #define HAL_STEP_TIMER_ISR  void TC3_Handler()
 #define HAL_TEMP_TIMER_ISR  void TC4_Handler()
 
+#define PULSE_TIMER_NUM STEP_TIMER_NUM
+#define PULSE_TIMER_PRESCALE STEPPER_TIMER_PRESCALE
+
 // --------------------------------------------------------------------------
 // Types
 // --------------------------------------------------------------------------

Marlin/src/HAL/HAL_LPC1768/HAL_timers.h

 #define HAL_TEMP_TIMER_RATE    1000000
 #define TEMP_TIMER_FREQUENCY   1000 // temperature interrupt frequency
 
+#define PULSE_TIMER_NUM STEP_TIMER_NUM
+#define PULSE_TIMER_PRESCALE STEPPER_TIMER_PRESCALE
+
 #define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(STEP_TIMER_NUM)
 #define DISABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_disable_interrupt(STEP_TIMER_NUM)
 #define ENABLE_TEMPERATURE_INTERRUPT() HAL_timer_enable_interrupt(TEMP_TIMER_NUM)

Marlin/src/HAL/HAL_STM32F1/HAL_timers_Stm32f1.h

 #define HAL_STEPPER_TIMER_RATE (HAL_TIMER_RATE / STEPPER_TIMER_PRESCALE)   // frequency of stepper timer (HAL_TIMER_RATE / STEPPER_TIMER_PRESCALE)
 #define HAL_TICKS_PER_US       ((HAL_STEPPER_TIMER_RATE) / 1000000) // stepper timer ticks per us
 
+#define PULSE_TIMER_NUM STEP_TIMER_NUM
+#define PULSE_TIMER_PRESCALE STEPPER_TIMER_PRESCALE
+
 #define TEMP_TIMER_PRESCALE     1000 // prescaler for setting Temp timer, 72Khz
 #define TEMP_TIMER_FREQUENCY    1000 // temperature interrupt frequency
 

Marlin/src/HAL/HAL_TEENSY35_36/HAL_timers_Teensy.h

 #define STEPPER_TIMER STEP_TIMER_NUM // Alias?
 #define STEPPER_TIMER_PRESCALE 0 // Not defined anywhere else!
 
+#define PULSE_TIMER_NUM STEP_TIMER_NUM
+#define PULSE_TIMER_PRESCALE STEPPER_TIMER_PRESCALE
+
 #define HAL_TIMER_RATE         (FTM0_TIMER_RATE)
 #define HAL_STEPPER_TIMER_RATE HAL_TIMER_RATE
 #define HAL_TICKS_PER_US       ((HAL_STEPPER_TIMER_RATE) / 1000000)

Marlin/src/module/stepper.cpp

      * 10µs = 160 or 200 cycles.
      */
     #if EXTRA_CYCLES_XYZE > 20
-      hal_timer_t pulse_start = HAL_timer_get_current_count(STEP_TIMER_NUM);
+      hal_timer_t pulse_start = HAL_timer_get_current_count(PULSE_TIMER_NUM);
     #endif
 
     #if HAS_X_STEP
 
     // For minimum pulse time wait before stopping pulses
     #if EXTRA_CYCLES_XYZE > 20
-      while (EXTRA_CYCLES_XYZE > (uint32_t)(HAL_timer_get_current_count(STEP_TIMER_NUM) - pulse_start) * (STEPPER_TIMER_PRESCALE)) { /* nada */ }
-      pulse_start = HAL_timer_get_current_count(STEP_TIMER_NUM);
+      while (EXTRA_CYCLES_XYZE > (uint32_t)(HAL_timer_get_current_count(PULSE_TIMER_NUM) - pulse_start) * (PULSE_TIMER_PRESCALE)) { /* nada */ }
+      pulse_start = HAL_timer_get_current_count(PULSE_TIMER_NUM);
     #elif EXTRA_CYCLES_XYZE > 0
       DELAY_NOPS(EXTRA_CYCLES_XYZE);
     #endif
 
     // For minimum pulse time wait after stopping pulses also
     #if EXTRA_CYCLES_XYZE > 20
-      if (i) while (EXTRA_CYCLES_XYZE > (uint32_t)(HAL_timer_get_current_count(STEP_TIMER_NUM) - pulse_start) * (STEPPER_TIMER_PRESCALE)) { /* nada */ }
+      if (i) while (EXTRA_CYCLES_XYZE > (uint32_t)(HAL_timer_get_current_count(PULSE_TIMER_NUM) - pulse_start) * (PULSE_TIMER_PRESCALE)) { /* nada */ }
     #elif EXTRA_CYCLES_XYZE > 0
       if (i) DELAY_NOPS(EXTRA_CYCLES_XYZE);
     #endif
     for (uint8_t i = step_loops; i--;) {
 
       #if EXTRA_CYCLES_E > 20
-        hal_timer_t pulse_start = HAL_timer_get_current_count(STEP_TIMER_NUM);
+        hal_timer_t pulse_start = HAL_timer_get_current_count(PULSE_TIMER_NUM);
       #endif
 
       START_E_PULSE(0);
 
       // For minimum pulse time wait before stopping pulses
       #if EXTRA_CYCLES_E > 20
-        while (EXTRA_CYCLES_E > (hal_timer_t)(HAL_timer_get_current_count(STEP_TIMER_NUM) - pulse_start) * (STEPPER_TIMER_PRESCALE)) { /* nada */ }
-        pulse_start = HAL_timer_get_current_count(STEP_TIMER_NUM);
+        while (EXTRA_CYCLES_E > (hal_timer_t)(HAL_timer_get_current_count(PULSE_TIMER_NUM) - pulse_start) * (PULSE_TIMER_PRESCALE)) { /* nada */ }
+        pulse_start = HAL_timer_get_current_count(PULSE_TIMER_NUM);
       #elif EXTRA_CYCLES_E > 0
         DELAY_NOPS(EXTRA_CYCLES_E);
       #endif
 
       // For minimum pulse time wait before looping
       #if EXTRA_CYCLES_E > 20
-        if (i) while (EXTRA_CYCLES_E > (hal_timer_t)(HAL_timer_get_current_count(STEP_TIMER_NUM) - pulse_start) * (STEPPER_TIMER_PRESCALE)) { /* nada */ }
+        if (i) while (EXTRA_CYCLES_E > (hal_timer_t)(HAL_timer_get_current_count(PULSE_TIMER_NUM) - pulse_start) * (PULSE_TIMER_PRESCALE)) { /* nada */ }
       #elif EXTRA_CYCLES_E > 0
         if (i) DELAY_NOPS(EXTRA_CYCLES_E);
       #endif
 
   #if EXTRA_CYCLES_BABYSTEP > 20
     #define _SAVE_START const hal_timer_t pulse_start = HAL_timer_get_current_count(STEP_TIMER_NUM)
-    #define _PULSE_WAIT while (EXTRA_CYCLES_BABYSTEP > (uint32_t)(HAL_timer_get_current_count(STEP_TIMER_NUM) - pulse_start) * (STEPPER_TIMER_PRESCALE)) { /* nada */ }
+    #define _PULSE_WAIT while (EXTRA_CYCLES_BABYSTEP > (uint32_t)(HAL_timer_get_current_count(STEP_TIMER_NUM) - pulse_start) * (PULSE_TIMER_PRESCALE)) { /* nada */ }
   #else
     #define _SAVE_START NOOP
     #if EXTRA_CYCLES_BABYSTEP > 0