Bug#17228383: VALGRIND WARNING IN IBUF_DELETE_REC

Since the mtr_t struct is marked as invalid in DEBUG_VALGRIND build
during mtr_commit, checking mtr->inside_ibuf will cause this warning.
Also since mtr->inside_ibuf cannot be set in mtr_commit (assert check)
and mtr->state is set to MTR_COMMITTED, the 'ut_ad(!ibuf_inside(&mtr))'
check is not needed if 'ut_ad(mtr.state == MTR_COMMITTED)' is also
checked.

storage/innobase/ibuf/ibuf0ibuf.c

@@ -4373,7 +4373,6 @@ ibuf_delete_rec(
 			      BTR_MODIFY_TREE, pcur, mtr)) {
 
 		mutex_exit(&ibuf_mutex);
-		ut_ad(!ibuf_inside(mtr));
 		ut_ad(mtr->state == MTR_COMMITTED);
 		goto func_exit;
 	}
@@ -4394,7 +4393,6 @@ ibuf_delete_rec(
 	ibuf_btr_pcur_commit_specify_mtr(pcur, mtr);
 
 func_exit:
-	ut_ad(!ibuf_inside(mtr));
 	ut_ad(mtr->state == MTR_COMMITTED);
 	btr_pcur_close(pcur);
 
@@ -4731,7 +4729,6 @@ ibuf_merge_or_delete_for_page(
 						      BTR_MODIFY_LEAF,
 						      &pcur, &mtr)) {
 
-					ut_ad(!ibuf_inside(&mtr));
 					ut_ad(mtr.state == MTR_COMMITTED);
 					mops[op]++;
 					ibuf_dummy_index_free(dummy_index);