xfs: Convert sync_page_range() to simple filemap_write_and_wait_range()

Christoph Hellwig says that it is enough for XFS to call
filemap_write_and_wait_range() instead of sync_page_range() because we do
all the metadata syncing when forcing the log.

CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/xfs/linux-2.6/xfs_lrw.c

@@ -817,7 +817,8 @@ xfs_write(
 		xfs_iunlock(xip, iolock);
 		if (need_i_mutex)
 			mutex_unlock(&inode->i_mutex);
-		error2 = sync_page_range(inode, mapping, pos, ret);
+		error2 = filemap_write_and_wait_range(mapping, pos,
+						      pos + ret - 1);
 		if (!error)
 			error = error2;
 		if (need_i_mutex)