bcachefs: fast exit when darray_make_room failed

In downgrade_table_extra, the return value is needed. When it
return failed, we should exit immediately.

Fixes: 7773df1 ("bcachefs: metadata version bucket_stripe_sectors")
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Author: Hongbo Li

fs/bcachefs/sb-downgrade.c

@@ -353,7 +353,9 @@ int bch2_sb_downgrade_update(struct bch_fs *c)
 		for (unsigned i = 0; i < src->nr_errors; i++)
 			dst->errors[i] = cpu_to_le16(src->errors[i]);
 
-		downgrade_table_extra(c, &table);
+		ret = downgrade_table_extra(c, &table);
+		if (ret)
+			goto out;
 
 		if (!dst->recovery_passes[0] &&
 		    !dst->recovery_passes[1] &&