drm/i915: Compute per-crtc min_cdclk earlier

drm/i915: Compute per-crtc min_cdclk earlier

Currently we compute the min_cdclk for each pipe during
intel_cdclk_atomic_check(). But that is too late for the
pipe prefill vs. vblank length checks (done during
intel_compute_global_watermarks).

We can't just reorder these things due to other dependencies,
so instead pull only the per-crtc minimum cdclk calculation
ahead. We should have enough information for that as soon
as we've computed the min cdclk for the planes.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20251013201236.30084-8-ville.syrjala@linux.intel.com
Reviewed-by: Mika Kahola <mika.kahola@intel.com>