Postmortem Debugging to serial port (#20492)

Marlin/src/HAL/ESP32/inc/SanityCheck.h

@@ -30,9 +30,13 @@
 #endif
 
 #if HAS_TMC_SW_SERIAL
-  #error "TMC220x Software Serial is not supported on this platform."
+  #error "TMC220x Software Serial is not supported on ESP32."
 #endif
 
 #if BOTH(WIFISUPPORT, ESP3D_WIFISUPPORT)
   #error "Only enable one WiFi option, either WIFISUPPORT or ESP3D_WIFISUPPORT."
 #endif
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  #error "POSTMORTEM_DEBUGGING is not yet supported on ESP32."
+#endif