drm/i915/color: Extract intel_color_modeset()

drm/i915/color: Extract intel_color_modeset()

[ Upstream commit 84d2d0430f0833cdf52a3d051906add051f20ef0 ]

We always perform the same steps to program color management
stuff during a full modeset. Extract that code to a helper
to avoid duplication.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240916152958.17332-2-ville.syrjala@linux.intel.com
Reviewed-by: Luca Coelho <luciano.coelho@intel.com>
Stable-dep-of: 30bfc151f0c1 ("drm/xe: Remove double pageflip")
Signed-off-by: Sasha Levin <sashal@kernel.org>