Add JNI_OnLoad to dynamic API

src/dynapi/SDL_dynapi_overrides.h

@@ -1282,3 +1282,4 @@
 #define SDL_hid_get_properties SDL_hid_get_properties_REAL
 #define SDL_GetPixelFormatFromGPUTextureFormat SDL_GetPixelFormatFromGPUTextureFormat_REAL
 #define SDL_GetGPUTextureFormatFromPixelFormat SDL_GetGPUTextureFormatFromPixelFormat_REAL
+#define JNI_OnLoad JNI_OnLoad_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -1290,3 +1290,4 @@ SDL_DYNAPI_PROC(Uint32,SDL_AddAtomicU32,(SDL_AtomicU32 *a,int b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_PropertiesID,SDL_hid_get_properties,(SDL_hid_device *a),(a),return)
 SDL_DYNAPI_PROC(SDL_PixelFormat,SDL_GetPixelFormatFromGPUTextureFormat,(SDL_GPUTextureFormat a),(a),return)
 SDL_DYNAPI_PROC(SDL_GPUTextureFormat,SDL_GetGPUTextureFormatFromPixelFormat,(SDL_PixelFormat a),(a),return)
+SDL_DYNAPI_PROC(Sint32,JNI_OnLoad,(JavaVM *a, void *b),(a,b),return)