drm/i915: Remove the "vblank delay" state dump

drm/i915: Remove the "vblank delay" state dump

The "vblank delay" we are including in the crtc state dump is
meaningful only when running with fixed refresh rate timings.
With VRR timings one has to look at the VRR state to figure out
the same thing.

Since we already dump the position of the delayed vblank for
both fixed refresh rate and VRR timings, this "vblank delay"
thing seems pretty much pointless now. Get rid of it.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20251020185038.4272-4-ville.syrjala@linux.intel.com
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>