btrfs: tree-checker: add missing returns after data_ref alignment checks

There are sectorsize alignment checks that are reported but then
check_extent_data_ref continues. This was not intended, wrong alignment
is not a minor problem and we should return with error.

CC: stable@vger.kernel.org # 5.4+
Fixes: 0785a9aa ("btrfs: tree-checker: Add EXTENT_DATA_REF check")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>