drm/amd/display: Map ODM memory correctly when doing ODM combine

drm/amd/display: Map ODM memory correctly when doing ODM combine

[why]
Up to 4 ODM memory pieces are required per ODM combine and cannot
overlap, i.e. each ODM "session" has to use its own memory pieces.
The ODM-memory mapping is currently broken for generic case.

The maximum number of memory pieces is ASIC-dependent, but it's always
big enough to satisfy maximum number of ODM combines. Memory pieces
are mapped as a bit-map, i.e. one memory piece corresponds to one bit.
The OPTC doing ODM needs to select memory pieces by setting the
corresponding bits, making sure there's no overlap with other OPTC
instances that might be doing ODM.

The current mapping works only for OPTC instance indexes smaller than
3. For instance indexes 3 and up it practically maps no ODM memory,
causing black, gray or white screen in display configs that include
ODM on OPTC instance 3 or up.

[how]
Statically map two unique ODM memory pieces for each OPTC instance
and piece them together when programming ODM combine mode.

Signed-off-by: Nikola Cornij <nikola.cornij@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>