drm/amd/display: always reset ODM mode in context when adding first plane

[why]
In current implemenation ODM mode is only reset when the last plane is
removed from dc state. For any dc validate we will always remove all
current planes and add new planes. However when switching from no planes
to 1 plane, ODM mode is not reset because no planes get removed. This
has caused an issue where we kept ODM combine when it should have been
remove when a plane is added. The change is to reset ODM mode when
adding the first plane.

Cc: stable@vger.kernel.org
Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>