media: v4l2-ctrls.h: fix wrong copy-and-paste comment

The __v4l2_ctrl_modify_range is the unlocked variant, so the comment about
taking a lock is obviously wrong.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>