[experimental] v6.7.6

Update graysky2's compiler optimization patches for 5.17-6.1.78, 6.1.…

…79-6.8-rc3 qnd 6.8-rc4+

The 6.1.79-6.8-rc3 patch doesn't apply against 6.8-rc1, rc2 and rc3, so let's only apply the 6.8-rc4+ patch against 6.8rc. It applies fine against 6.8-rc5.

Fixes https://github.com/Frogging-Family/linux-tkg/issues/889