xfs: remove dead ENODEV handling in xfs_destroy_ioend

No driver returns ENODEV from it bio completion handler, not has this
ever been documented.  Remove the dead code dealing with it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

fs/xfs/xfs_aops.c

@@ -122,17 +122,6 @@ xfs_destroy_ioend(
 		bh->b_end_io(bh, !ioend->io_error);
 	}
 
-	/*
-	 * Volume managers supporting multiple paths can send back ENODEV
-	 * when the final path disappears.  In this case continuing to fill
-	 * the page cache with dirty data which cannot be written out is
-	 * evil, so prevent that.
-	 */
-	if (unlikely(ioend->io_error == -ENODEV)) {
-		xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ,
-				      __FILE__, __LINE__);
-	}
-
 	xfs_ioend_wake(ip);
 	mempool_free(ioend, xfs_ioend_pool);
 }