jfs: Convert drop_metapage and remove_metapage to take a folio

All callers now have a folio, so pass it in instead of the page.
Removes a couple of calls to compound_head().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>