btrfs: compare the correct fsid/metadata_uuid in btrfs_validate_super

btrfs: compare the correct fsid/metadata_uuid in btrfs_validate_super

The function btrfs_validate_super() should verify the metadata_uuid in
the provided superblock argument. Because, all its callers expect it to
do that.

Such as in the following stacks:

  write_all_supers()
   sb = fs_info->super_for_commit;
   btrfs_validate_write_super(.., sb)
     btrfs_validate_super(.., sb, ..)

  scrub_one_super()
	btrfs_validate_super(.., sb, ..)

And
   check_dev_super()
	btrfs_validate_super(.., sb, ..)

However, it currently verifies the fs_info::super_copy::metadata_uuid
instead.  Fix this using the correct metadata_uuid in the superblock
argument.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>