[XFRM]: fix sparse gfp nocast warnings

Fix implicit nocast warnings in xfrm code:
net/xfrm/xfrm_policy.c:232:47: warning: implicit cast to nocast type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/xfrm.h

@@ -875,7 +875,7 @@ static inline int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsig
 } 
 #endif
 
-struct xfrm_policy *xfrm_policy_alloc(int gfp);
+struct xfrm_policy *xfrm_policy_alloc(unsigned int __nocast gfp);
 extern int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), void *);
 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
 struct xfrm_policy *xfrm_policy_bysel(int dir, struct xfrm_selector *sel,

net/xfrm/xfrm_policy.c

@@ -225,7 +225,7 @@ static void xfrm_policy_timer(unsigned long data)
  * SPD calls.
  */
 
-struct xfrm_policy *xfrm_policy_alloc(int gfp)
+struct xfrm_policy *xfrm_policy_alloc(unsigned int __nocast gfp)
 {
 	struct xfrm_policy *policy;