drm/i915/display: stop passing i to for_each_pipe_crtc_modeset_{enable, disable}()

drm/i915/display: stop passing i to for_each_pipe_crtc_modeset_{enable, disable}()

Refactor for_each_pipe_crtc_modeset_{enable,disable}() and their
underlying for_each_crtc_in_masks{,_reverse}() helpers to utilize
__UNIQUE_ID() to avoid having to pass the for loop variable to them.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/2270d4a10663bb55d5b16902b02798234f440517.1778659089.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>