fs: Add aops->dirty_folio

This replaces ->set_page_dirty().  It returns a bool instead of an int
and takes the address_space as a parameter instead of expecting the
implementations to retrieve the address_space from the page.  This is
particularly important for filesystems which use FS_OPS for swap.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs