Add missing include

src/arch_esp32.h

@@ -20,6 +20,7 @@
 #include <esp_ota_ops.h>   // Use angle brackets to avoid
 #include <esp_timer.h>     // amalgamation ditching them
 #include <esp_system.h>
+#include <esp_mac.h>
 
 #define MG_PATH_MAX 128