Enable --escape-exit for all relevant platforms. It makes PPSSPP more front-end friendly by letting escape quit the emu.
Fix Linux build.
Instead of using escape only, allow anything mapped to "Pause" to exit as well.
Fix Linux build, again.
Merge pull request #5959 from thedax/escapeEditOption

Enable --escape-exit for all relevant (e.g. non-mobile) platforms.