storage: Declare a private bootstrap for NDA user storage

src/storage/SDL_storage.c

@@ -34,6 +34,9 @@ static TitleStorageBootStrap *titlebootstrap[] = {
 static UserStorageBootStrap *userbootstrap[] = {
 #ifdef SDL_STORAGE_STEAM
     &STEAM_userbootstrap,
+#endif
+#ifdef SDL_STORAGE_PRIVATE
+    &PRIVATE_userbootstrap,
 #endif
     &GENERIC_userbootstrap,
     NULL

src/storage/SDL_sysstorage.h

@@ -44,6 +44,7 @@ extern TitleStorageBootStrap GENERIC_titlebootstrap;
 // Steam does not have title storage APIs
 
 extern UserStorageBootStrap GENERIC_userbootstrap;
+extern UserStorageBootStrap PRIVATE_userbootstrap;
 extern UserStorageBootStrap STEAM_userbootstrap;
 
 extern SDL_Storage *GENERIC_OpenFileStorage(const char *path);