drm/i915: Replace double blank with single blank after comma in gem/ and gt/

Do not use double blanks, ",  " in function parameters where it's
not required by any alignment purpose. Replase it with a single
blank, ", ".

Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240807130516.491053-2-andi.shyti@linux.intel.com