ext4: Remove PAGE_MASK dependency on mpage_submit_folio

This patch simply removes the PAGE_MASK dependency since
mpage_submit_folio() is already converted to work with folio.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/d6eadb090334ea49ceef4e643b371fabfcea328f.1709182251.git.ritesh.list@gmail.com


Signed-off-by: Theodore Ts'o <tytso@mit.edu>