[Wii] added game auto-load support through DOL args (compatible with "Wiiflow"
plugin arguments)
NOTE: if "loader" argument is sent, return to loader stub will automatically be
allowed either from Exit menu or using Wiimote POWER button
[Wii] fixed compilation warnings
Merge https://github.com/libretro/Genesis-Plus-GX
[Core/MD] disable cartridge backup RAM when mapped as volatile RAM over internal RAM ("Feng Kuang Tao Hua Yuan" crash)