SUNRPC: Defer deleting the security context until gss_do_free_ctx()

There is no need to delete the gss context separately from the rest
of the security context information, and doing so gives rise to a
an rcu_dereference_check() warning.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/auth_gss/auth_gss.c

@@ -928,6 +928,7 @@ gss_do_free_ctx(struct gss_cl_ctx *ctx)
 {
 	dprintk("RPC:       gss_free_ctx\n");
 
+	gss_delete_sec_context(&ctx->gc_gss_ctx);
 	kfree(ctx->gc_wire_ctx.data);
 	kfree(ctx);
 }
@@ -942,13 +943,7 @@ gss_free_ctx_callback(struct rcu_head *head)
 static void
 gss_free_ctx(struct gss_cl_ctx *ctx)
 {
-	struct gss_ctx *gc_gss_ctx;
-
-	gc_gss_ctx = rcu_dereference(ctx->gc_gss_ctx);
-	rcu_assign_pointer(ctx->gc_gss_ctx, NULL);
 	call_rcu(&ctx->gc_rcu, gss_free_ctx_callback);
-	if (gc_gss_ctx)
-		gss_delete_sec_context(&gc_gss_ctx);
 }
 
 static void