My branch might not compile for RPi3 as I've never focused to keep other projects compiling. If you look carefully, you will see that my 2016-12-01 branch is based on official LE master. You need almost all commits from my branch to build properly for MK808. I have no experience at all in compiling Dolphin-Emu, I can't help you. CEC will be looked into as soon as my buildserver goes back to life.
Been trying compiling LibreELEC-7.0 branch for RPi2. Finally succeeded in compiling and boots up OK. Unfortunately, I can't seem to attach the two patches. First is a patch to kodi-001-jarvis-rbp-backports.patch in projects/RPi2/patches/kodi, the "ffmpeg: test: increase number of threads" patch in commit f69190f fails, and consequently compilation of kodi fails. Second is patch to config/arch.arm, which is a revert of "[arm] go thumb!" commit f52e282, otherwise LibreELEC compiles but there is a kernel panic on boot. Pardon my possibly silly question, but what does the "go thumb!" supposed to do? I don't think it is in the main LibreELEC branch. With these 2 patches, all my 3 devices (RPi2, MK808B+ and x86_64) compile and boot up into LibreELEC OK.
I have not tried the krypton branches - CEC not working on my MK808B+ is too much of a problem for me. I might try compiling when the CEC issue is resolved. I don't think it is resolved yet?
As for dolphin-emu, I now have it compiling for both the LibreELEC-7.0 and krypton branches for x86_64, but have not tested it properly yet. Ultimately, I would like to have it running on my Intel i3 HTPC.
Once again, thank you for your fantastic work!