Renamed esp32-p4 to esp32-p4-devkit, to match esp32-s3-devkit

Perhaps they should be named:
- esp32-s3-generic / esp32-p4-generic
- esp32-s3-devboard / esp32-p4-devboard
- esp32-s3-template / esp32-p4-template

? I really don't know...

Author: ducalex

components/retro-go/targets/esp32-p4/config.h renamed to components/retro-go/targets/esp32-p4-devkit/config.h

@@ -6,7 +6,7 @@
 /****************************************************************************
  * Target definition for ESP32-P4 Dev-Board                                 *
  ****************************************************************************/
-#define RG_TARGET_NAME             "ESP32-P4"
+#define RG_TARGET_NAME             "ESP32-P4-DEVKIT"
 
 
 /****************************************************************************