drm/i915/cdclk: Do intel_cdclk_update_crtc_min_cdclk() per-pipe

drm/i915/cdclk: Do intel_cdclk_update_crtc_min_cdclk() per-pipe

Currently we call intel_cdclk_update_crtc_min_cdclk() per-plane.
That is rather wasteful, and also won't account for any of the
other per-pipe min_cdclk restrictions from
intel_crtc_compute_min_cdclk(). Change the behaviour to do
do the comparison per-crtc instead, and use the final min cdclk
as computed by intel_crtc_compute_min_cdclk().

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250923171943.7319-13-ville.syrjala@linux.intel.com
Reviewed-by: Mika Kahola <mika.kahola@intel.com>