drm/amd/display: Only update output transfer function for full type.

dcn10_translate_regamma_to_hw_format costs 750us to run, it cannot be
called within isr, check update flag before calling, only do it for
full update.

Signed-off-by: Yongqiang Sun <yongqiang.sun@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>