(Menu) "Start Core" for non-content cores

[RobLoach]

Cores like ScummVM or Mr.Boom can be run without content. Once a Core is successfully loaded, cores that support no-content should be able to use "Start Core".

QA

1. Load ScummVM, or via the command line ./ludo -L scummvm_libretro.so
2. See that the ScummVM GUI pops up

[kivutar]

How about we just start the core in Load Core if a core doesn't support content? Is there a way to detect this?

[RobLoach]

Great idea... So when you use Load Core --> ScummVM, it'll just boot straight into ScummVM.

It could be done with a check against what was passed in for the RETRO_ENVIRONMENT_SET_SUPPORT_NO_GAME environment call. When the core provides true for RETRO_ENVIRONMENT_SET_SUPPORT_NO_GAME, it should just start the core.