SUNRPC: fix compile warnings on 64-bit platforms

Introduced by NFS metrics patch.

Test plan:
Compile kernel with CONFIG_NFS enabled on a 64-bit platform.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/stats.c

@@ -186,7 +186,7 @@ void _print_name(struct seq_file *seq, unsigned int op, struct rpc_procinfo *pro
 		seq_printf(seq, "\t%12u: ", op);
 }
 
-#define MILLISECS_PER_JIFFY	(1000UL / HZ)
+#define MILLISECS_PER_JIFFY	(1000 / HZ)
 
 void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt)
 {