drm/amd/display: call set csc_default if enable adjustment is false

Fixes a greenish tint on RV displays.

Signed-off-by: Yue Hin Lau <Yuehin.Lau@amd.com>
Reviewed-by: Eric Bernstein <Eric.Bernstein@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[drake@endlessm.com: backport to 4.15]
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>