Merge pull request #23 from mscherer/fix_libretro_detection

Let libretro use the right region depending on the cartridge

platforms/libretro/libretro.cpp

@@ -339,7 +339,7 @@ void retro_unload_game(void)
 
 unsigned retro_get_region(void)
 {
-    return RETRO_REGION_NTSC;
+    return core->GetCartridge()->IsPAL() ? RETRO_REGION_PAL : RETRO_REGION_NTSC;
 }
 
 bool retro_load_game_special(unsigned type, const struct retro_game_info *info, size_t num)