drm/amd/display: Fix regression in dce110_apply_ctx_for_surfaces

Caused by "add programming for 0 plane case" which was tested on DCN but
not on DCE.

Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>