GameMode for RetroArch on Trimui

[Ultrahead]

Currently, GameMode cannot be used on RetroArch for systems like Trimui series, where it is not included. This prevent us from using the daemon for challenging emulations for the system, like the Atari Jaguar.

It would be handy if GameMode could be added to RetroArch for systems like the Trimui Smart Pro (and the recently-released the Trimui Brick).

No alternatives are on sight, other than waiting for a new version of the emulator (in this case, "Virtual Jaguar").