drm/amd/display: add odm split logic to scaling calculations

Currently odm scaling calculations are only done when adding initial
odm pipe. Any scaling re-calculations will mess up odm because of this.

This change resolves the problem by updating scaling split logic to
handle odm.

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Michael Strauss <Michael.Strauss@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>