this is a maintenance update for platforms not yet ported to 4.x branch
- update RetroArch to 1.10.1
- update cores on par with Lakka 4.0 in branch Lakka-v4.x
- bump Lakka version to 3.7.1
- add PKG_SKIP_SUBMODULE variable (pcsx_rearmed has obsolete submodule
registration, which breaks cloning the repo and pulling submodules)
- bump cmake to 3.15.0 (required by play)
* update libretro cores
* update atari800
* update tic80
* fix indent
* disable threaded renderer on arm
* update ignore sdl patch
* make: fix compile issues and update package from LE
* duckstation: repoint to libretro and update. upstream doesn't support libretro core anymore
* pcsx_rearmed: updated and removed unneeded patch
* libretro cores: update all cores
* melonds: fix patch error
* lutro: drop unneeded patch and update
* mu: revert back to make and fix directory references for building/copying core
* beetle-psx: pick version before static c++ until figure out linking
* bsnes2014: fix up copy build error
* bsnes-mercury: fixup copy build error
