radeon: fix pll/ctrc mapping on dce2 and dce3 hardware

This fix black screen on resume issue that some people are
experiencing. There is a bug in the atombios code regarding
pll/crtc mapping. The atombios code reverse the logic for
the pll and crtc mapping.

agd5f: drop unnecessary crtc id check, cc stable in case
we miss 3.7.

This fixes the root cause that was worked around by commits:
drm/radeon: allocate PPLLs from low to high
drm/radeon/dce3: switch back to old pll allocation order for discrete

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org