Factor out a function to modeset commit a set of pipes, which a later
patch will reuse for DP link retraining.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240610164933.2947366-6-imre.deak@intel.com