drm/i915: Fix ICL output CSC programming

drm/i915: Fix ICL output CSC programming

When I refactored the code into its own function I accidentally
misplaced the <<16 shifts for some of the registers causing us
to lose the blue channel entirely.

We should really find a way to test this...

Cc: Uma Shankar <uma.shankar@intel.com>
Fixes: d2c19b06d6ea ("drm/i915: Clean up ilk/icl pipe/output CSC programming")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190425192419.24931-1-ville.syrjala@linux.intel.com
Reviewed-by: Swati Sharma <swati2.sharma@intel.com>
(cherry picked from commit d428ca17ea3d307c5a7f77cf24586584bf1c2d74)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>