drm/amd/display: Request to have DCN RV pipe Harvesting

TODO: Current change only work for sucessive last fused pipe,
like p3, or p3,p2. It does not work for fused p1,p2.

Signed-off-by: Hersen Wu <hersenxs.wu@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>