SUNRPC: display human-readable procedure name in rpc_iostats output

Add fields to the rpc_procinfo struct that allow the display of a
human-readable name for each procedure in the rpc_iostats output.

Also fix it so that the NFSv4 stats are broken up correctly by
sub-procedure number.  NFSv4 uses only two real RPC procedures:
NULL, and COMPOUND.

Test plan:
Mount with NFSv2, NFSv3, and NFSv4, and do "cat /proc/self/mountstats".

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index 0edc03e..84ee39e 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -214,12 +214,16 @@
 		.p_encode	= (kxdrproc_t) xdr_encode_mon,
 		.p_decode	= (kxdrproc_t) xdr_decode_stat_res,
 		.p_bufsiz	= MAX(SM_mon_sz, SM_monres_sz) << 2,
+		.p_statidx	= SM_MON,
+		.p_name		= "MONITOR",
 	},
 [SM_UNMON] = {
 		.p_proc		= SM_UNMON,
 		.p_encode	= (kxdrproc_t) xdr_encode_unmon,
 		.p_decode	= (kxdrproc_t) xdr_decode_stat,
 		.p_bufsiz	= MAX(SM_mon_id_sz, SM_unmonres_sz) << 2,
+		.p_statidx	= SM_UNMON,
+		.p_name		= "UNMONITOR",
 	},
 };