emulators/ppsspp: Update to 1.20.2
- Remove emulators/ppsspp-qt5 due to Qt 5 being end of life
- Unbundle freetype, libchdr and rapidjson
- Remove redundant -msse2 compiler flag on amd64 as this is enabled by default
Changes submitted upstream, https://github.com/hrydgard/ppsspp/pull/21428
PR: 293572