drm/i915: Pass the plane to icl_program_input_csc_coeff()

drm/i915: Pass the plane to icl_program_input_csc_coeff()

On icl+ the plane state that gets passed to update_slave() is not
the plane state of the plane we're programming. With NV12 the
plane state would be coming from the master (UV) plane whereas
the plane we're programming is the slave (Y) plane. For that reason
we need to explicitly pass around the slave plane (or we'd have to
otherwise deduce it by checking whether we were called via
.update_plane() or .update_slave()).

In the case of icl_program_input_csc_coeff() it's actually OK to
assume that we are always the master plane because the input CSC
only exists on HDR planes which can never be a slave plane. But
for consistency let's pass in the plane explicitly anyway.

While at it drop the "_coeff" from the function name since it's
kinda redundant, and this makes the name a bit shorter :)

Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181114210729.16185-14-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>