AVR sanity check for MONITOR_DRIVER_STATUS with SW Serial (#16421)

Marlin/src/HAL/HAL_AVR/inc/SanityCheck.h

 #if HAS_TRINAMIC && ENABLED(ENDSTOP_INTERRUPTS_FEATURE)
   #error "TMCStepper includes SoftwareSerial.h which is incompatible with ENDSTOP_INTERRUPTS_FEATURE. Disable ENDSTOP_INTERRUPTS_FEATURE to continue."
 #endif
+
+#if TMC_HAS_SW_SERIAL && ENABLED(MONITOR_DRIVER_STATUS)
+  #error "MONITOR_DRIVER_STATUS causes performance issues when used with SoftwareSerial-connected drivers. Disable MONITOR_DRIVER_STATUS or use hardware serial to continue."
+#endif

buildroot/share/tests/megaatmega2560-tests

 opt_set LCD_LANGUAGE es
 opt_enable USE_ZMIN_PLUG FIX_MOUNTED_PROBE AUTO_BED_LEVELING_BILINEAR PAUSE_BEFORE_DEPLOY_STOW \
            MKS_12864OLED EEPROM_SETTINGS EEPROM_CHITCHAT M114_DETAIL \
-           MONITOR_DRIVER_STATUS STEALTHCHOP_XY STEALTHCHOP_Z STEALTHCHOP_E HYBRID_THRESHOLD SENSORLESS_HOMING SQUARE_WAVE_STEPPING
+           STEALTHCHOP_XY STEALTHCHOP_Z STEALTHCHOP_E HYBRID_THRESHOLD SENSORLESS_HOMING SQUARE_WAVE_STEPPING
 opt_set X_MAX_ENDSTOP_INVERTING false
 opt_set X_DRIVER_TYPE TMC2209
 opt_set Y_DRIVER_TYPE TMC2130