For the experimental NFS client, it should always flush dirty

buffers before closing the NFSv4 opens, as the comment states.
This patch deletes the call to nfscl_mustflush() which would
return 0 for the case where a delegation still exists, which
was incorrect and could cause crashes during recovery from
an expired lease.

MFC after:	1 week

sys/fs/nfsclient/nfs_clnode.c

@@ -198,7 +198,6 @@ ncl_inactive(struct vop_inactive_args *ap)
 		 * must be flushed before the close, so that the stateid is
 		 * available for the writes.
 		 */
-		if (nfscl_mustflush(vp))
 		(void) ncl_flush(vp, MNT_WAIT, NULL, ap->a_td, 1, 0);
 		(void) nfsrpc_close(vp, 1, ap->a_td);
 	}