drm/i915/display: remove explicit CNL handling from intel_color.c

The only real platform with DISPLAY_VER == 10 is GLK, so we don't need
any checks and supporting code for CNL. For DISPLAY_VER >= 11,
ilk_load_csc_matrix() is not used, so make it handle GLK only.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210728215946.1573015-4-lucas.demarchi@intel.com

drivers/gpu/drm/i915/display/intel_color.c

@@ -305,13 +305,12 @@ static void ilk_load_csc_matrix(const struct intel_crtc_state *crtc_state)
 				    ilk_csc_postoff_limited_range);
 	} else if (crtc_state->csc_enable) {
 		/*
-		 * On GLK+ both pipe CSC and degamma LUT are controlled
+		 * On GLK both pipe CSC and degamma LUT are controlled
 		 * by csc_enable. Hence for the cases where the degama
 		 * LUT is needed but CSC is not we need to load an
 		 * identity matrix.
 		 */
-		drm_WARN_ON(&dev_priv->drm, !IS_CANNONLAKE(dev_priv) &&
-			    !IS_GEMINILAKE(dev_priv));
+		drm_WARN_ON(&dev_priv->drm, !IS_GEMINILAKE(dev_priv));
 
 		ilk_update_pipe_csc(crtc, ilk_csc_off_zero,
 				    ilk_csc_coeff_identity,