drm/i915: Split ilk vs. icl csc matrix handling

drm/i915: Split ilk vs. icl csc matrix handling

Split the csc matrix handling to ilk+ and icl+ functions.
This keeps the logic clear on what is loaded into which
CSC unit on the hardware.

We also fix the icl+ code to load the full->limited range
conversion matrix into the output CSC rather than the pipe
CSC which was used on earlier platforms. And we also turn
on the pipe CSC only when the ctm is present.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190218193137.22914-8-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>