✨ ESP32 Panda_ZHU and Panda_M4 (#22644)

Marlin/src/HAL/AVR/HAL_SPI.cpp

@@ -34,7 +34,9 @@
 #include "../../inc/MarlinConfig.h"
 
 void spiBegin() {
-  OUT_WRITE(SD_SS_PIN, HIGH);
+  #if PIN_EXISTS(SD_SS)
+    OUT_WRITE(SD_SS_PIN, HIGH);
+  #endif
   SET_OUTPUT(SD_SCK_PIN);
   SET_INPUT(SD_MISO_PIN);
   SET_OUTPUT(SD_MOSI_PIN);