[RPC]: fix sparse gfp nocast warnings

Fix nocast sparse warnings:
net/rxrpc/call.c:2013:25: warning: implicit cast to nocast type
net/rxrpc/connection.c:538:46: warning: implicit cast to nocast type
net/sunrpc/sched.c:730:36: warning: implicit cast to nocast type
net/sunrpc/sched.c:734:56: warning: implicit cast to nocast type

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index f310403..ade730e 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -719,7 +719,7 @@
 void *
 rpc_malloc(struct rpc_task *task, size_t size)
 {
-	int	gfp;
+	unsigned int __nocast	gfp;
 
 	if (task->tk_flags & RPC_TASK_SWAPPER)
 		gfp = GFP_ATOMIC;