drm/i915/vrr: Use trans_vrr_ctl() in intel_vrr_transcoder_disable()

drm/i915/vrr: Use trans_vrr_ctl() in intel_vrr_transcoder_disable()

Currently intel_vrr_disable() writes TRANS_VRR_CTL() with
trans_vrr_ctl(), whereas intel_vrr_transcoder_disable() always
writes just a plain 0. Write trans_vrr_ctl() in both places to
unify the code, allowing for more shared code in the future.

Since the VRR timing generator will be disabled by the
TRANS_VRR_CTL write it doesn't really matter what we write to
the register (other than VRR_CTL_VRR_ENABLE that is).

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20251020185038.4272-12-ville.syrjala@linux.intel.com
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>