drm/amd/display: Revert "Fallback to SW cursor if SubVP + cursor too big"

drm/amd/display: Revert "Fallback to SW cursor if SubVP + cursor too big"

This reverts commit 3db3b902a6ec5f5f2e6c94883a10e4e70021a058 since
returning false in case of SubVP results in no cursor being visible on
desktop as there is no sw cursor fallback path on all platforms.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Alvin Lee <Alvin.Lee2@amd.com>
Acked-by: Pavle Kotarac <Pavle.Kotarac@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>