mm/hugetlb: assert hugetlb_lock in __hugetlb_cgroup_commit_charge

This is similar to __hugetlb_cgroup_uncharge_folio() where it relies on
holding hugetlb_lock. Add the similar assertion like the other one, since
it looks like such things may help some day.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Peter Xu <[e-mail]>
Reviewed-by: Mina Almasry <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: David Rientjes <[e-mail]>
Cc: Muchun Song <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

mm/hugetlb_cgroup.c

···
 {
 	if (hugetlb_cgroup_disabled() || !h_cg)
 		return;
-
+	lockdep_assert_held(&hugetlb_lock);
 	__set_hugetlb_cgroup(folio, h_cg, rsvd);
 	if (!rsvd) {
 		unsigned long usage =