drm/amd/display: add new pixel rate programming

[why]
New dividers in DCCG need to be programmed depending
on encoder/stream type since pixels per clock in
OTG/DIO is different

DIO also needs additional programming depending on
pixels per clock

Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>