Always clamp in ToRGB[A]?().

Before we only clamped with SSE, better to be consistent.  This may also
be slightly faster.
Missing include for Linux/etc.
And fix an issue building on Android.
Merge pull request #7035 from unknownbrackets/gpu-minor

Always clamp in ToRGB[A]?()
Merge https://github.com/hrydgard/ppsspp
Merge branch 'master' of https://github.com/libretro/ppsspp