[NETLINK]: Fix "nocast type" warnings

From: Victor Fusco <victor@cetuc.puc-rio.br>

Fix the sparse warning "implicit cast to nocast type"

Signed-off-by: Victor Fusco <victor@cetuc.puc-rio.br>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 3405fdf..ff774a0 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -648,7 +648,8 @@
 	sock_put(sk);
 }
 
-static inline struct sk_buff *netlink_trim(struct sk_buff *skb, int allocation)
+static inline struct sk_buff *netlink_trim(struct sk_buff *skb,
+					   unsigned int __nocast allocation)
 {
 	int delta;
 
@@ -717,7 +718,7 @@
 	int failure;
 	int congested;
 	int delivered;
-	int allocation;
+	unsigned int allocation;
 	struct sk_buff *skb, *skb2;
 };