SUNRPC: Mark auth and cred operation tables as constant.

Also do the same for gss_api operation tables.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/auth_null.c b/net/sunrpc/auth_null.c
index 890bd9b..fe9b6aa 100644
--- a/net/sunrpc/auth_null.c
+++ b/net/sunrpc/auth_null.c
@@ -101,7 +101,7 @@
 	return p;
 }
 
-struct rpc_authops authnull_ops = {
+const struct rpc_authops authnull_ops = {
 	.owner		= THIS_MODULE,
 	.au_flavor	= RPC_AUTH_NULL,
 #ifdef RPC_DEBUG
@@ -122,7 +122,7 @@
 };
 
 static
-struct rpc_credops	null_credops = {
+const struct rpc_credops null_credops = {
 	.cr_name	= "AUTH_NULL",
 	.crdestroy	= nul_destroy_cred,
 	.crmatch	= nul_match,