ext4: do not destroy ext4_groupinfo_caches if ext4_mb_init() fails

Caches from 'ext4_groupinfo_caches' may be in use by other mounts,
which have already existed.  So, it is incorrect to destroy them when
newly requested mount fails.

Found by Linux File System Verification project (linuxtesting.org).

Signed-off-by: Andrey Tsyvarev <tsyvarev@ispras.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index c8238a2..3235a2f 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2617,7 +2617,7 @@
 	sbi->s_locality_groups = alloc_percpu(struct ext4_locality_group);
 	if (sbi->s_locality_groups == NULL) {
 		ret = -ENOMEM;
-		goto out_free_groupinfo_slab;
+		goto out;
 	}
 	for_each_possible_cpu(i) {
 		struct ext4_locality_group *lg;
@@ -2642,8 +2642,6 @@
 out_free_locality_groups:
 	free_percpu(sbi->s_locality_groups);
 	sbi->s_locality_groups = NULL;
-out_free_groupinfo_slab:
-	ext4_groupinfo_destroy_slabs();
 out:
 	kfree(sbi->s_mb_offsets);
 	sbi->s_mb_offsets = NULL;