drm/i915/debugfs: Get rid of single use macros.

No good reason for these indirection cases.

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230120110658.1083757-1-rodrigo.vivi@intel.com