ntfs: convert ntfs_writepage to use a folio

Use folio APIs throughout.  Saves many hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231016201114.1928083-19-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>