drm/amd/display: fix odm 2:1 policy not being applied consistently in 4k144 modes

[Why]
odm 2:1 policy is splitting the pipes in 4k144.
then in subvp code, we merge the pipes. but since the
 configuration is unsupported, we keep the pipes split

[How]
for unsupported subvp configuration, redo the dml and
 pipe split calls

Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Samson Tam <samson.tam@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>