drm/amd/display: expose plane blend LUT in HW with MCM

drm/amd/display: expose plane blend LUT in HW with MCM

Since commit 39923050615cd ("drm/amd/display: Clear DPP 3DLUT Cap")
there is a flag in the mpc_color_caps that indicates the pre-blend usage
of MPC color caps. Do the same as commit 9e5d4a5e27c6 ("drm/amd/display:
Use mpc.preblend flag to indicate preblend") and use the mpc.preblend
flag to expose plane blend LUT/TF properties on AMD display driver.

CC: Matthew Schwartz <matthew.schwartz@linux.dev>
Signed-off-by: Melissa Wen <mwen@igalia.com>
Tested-by: Matthew Schwartz <matthew.schwartz@linux.dev>
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>