sunrpc: move pc_count out of struct svc_procinfo

pc_count is the only writeable memeber of struct svc_procinfo, which is
a good candidate to be const-ified as it contains function pointers.

This patch moves it into out out struct svc_procinfo, and into a
separate writable array that is pointed to by struct svc_version.

Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index a947dce..bad5fec 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2554,10 +2554,12 @@ static struct svc_procedure		nfsd_procedures4[2] = {
 	},
 };
 
+static unsigned int nfsd_count3[ARRAY_SIZE(nfsd_procedures4)];
 struct svc_version	nfsd_version4 = {
 	.vs_vers		= 4,
 	.vs_nproc		= 2,
 	.vs_proc		= nfsd_procedures4,
+	.vs_count		= nfsd_count3,
 	.vs_dispatch		= nfsd_dispatch,
 	.vs_xdrsize		= NFS4_SVC_XDRSIZE,
 	.vs_rpcb_optnl		= true,