Refactor TMC-related macros and sanity checks (#16384)

Marlin/src/HAL/HAL_STM32/HAL.cpp

@@ -28,13 +28,7 @@
 #include "../../inc/MarlinConfig.h"
 #include "../shared/Delay.h"
 
-#if (__cplusplus == 201703L) && defined(__has_include)
-  #define HAS_SWSERIAL __has_include(<SoftwareSerial.h>)
-#else
-  #define HAS_SWSERIAL HAS_TMC220x
-#endif
-
-#if HAS_SWSERIAL
+#if TMC_HAS_SW_SERIAL
   #include "SoftwareSerial.h"
 #endif
 
@@ -93,7 +87,7 @@ void HAL_init() {
   while (!LL_PWR_IsActiveFlag_BRR());
   #endif // EEPROM_EMULATED_SRAM
 
-  #if HAS_SWSERIAL
+  #if TMC_HAS_SW_SERIAL
     SoftwareSerial::setInterruptPriority(SWSERIAL_TIMER_IRQ_PRIO, 0);
   #endif
 }