xfs: writepage always has buffers

These days we always have buffers thanks to ->page_mkwrite.  And we
already have an assert a few lines above tripping in case that was
not true due to a bug.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>

fs/xfs/linux-2.6/xfs_aops.c

@@ -1072,13 +1072,6 @@ xfs_vm_writepage(
 	if ((current->flags & PF_FSTRANS) && (delalloc || unwritten))
 		goto out_fail;
 
-	/*
-	 * Delay hooking up buffer heads until we have
-	 * made our go/no-go decision.
-	 */
-	if (!page_has_buffers(page))
-		create_empty_buffers(page, 1 << inode->i_blkbits, 0);
-
 	/* Is this page beyond the end of the file? */
 	offset = i_size_read(inode);
 	end_index = offset >> PAGE_CACHE_SHIFT;