[Intel-gfx] Fastboot in 6 patches

[Jesse Barnes]

It grew a little...  but there's only one real hack left, and that's the
PFIT bits.  To fix that properly, I think either we need to pull the
compute_config calls out of set_mode and into its callers so we can
compare pfit state, or something more ambitious where we collect all the
new configs up front and then let set_mode figure out how to apply it
minimally to hw.

Hopefully the other patches are pretty close to being ready though...

Thanks,
Jesse