CFG_DEFAULTS

Use CFG_DEFAULTS to change the default config settings for different targets.

Mainly this is for the jolla phone, where both mupen64plus-input-sdl and my mupen64plus-input-sdltouch plugin will be shipped. I want users to be able to play out of the box using the sdltouch plugin and not make them have to edit the config file first. The sdl plugin is shipped for users who want to use for example bluetooth controllers but some users probably don't not have one.
Also mupen64plus-video-rice is broken on the jolla phone, so i've defaulted it to mupen64plus-video-glide64mk2.