dax: use sb_issue_zerout instead of calling dax_clear_sectors
dax_clear_sectors() cannot handle poisoned blocks. These must be
zeroed using the BIO interface instead. Convert ext2 and XFS to use
only sb_issue_zerout().
Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
[vishal: Also remove the dax_clear_sectors function entirely] Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>