[XFRM] xfrm_policy_destroy: Rename and relative fixes.

Since __xfrm_policy_destroy is used to destory the resources
allocated by xfrm_policy_alloc. So using the name
__xfrm_policy_destroy is not correspond with xfrm_policy_alloc.
Rename it to xfrm_policy_destroy.

And along with some instances that call xfrm_policy_alloc
but not using xfrm_policy_destroy to destroy the resource,
fix them.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index d83227b..534b29e 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -221,7 +221,7 @@
 
 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 
-void __xfrm_policy_destroy(struct xfrm_policy *policy)
+void xfrm_policy_destroy(struct xfrm_policy *policy)
 {
 	BUG_ON(!policy->dead);
 
@@ -233,7 +233,7 @@
 	security_xfrm_policy_free(policy);
 	kfree(policy);
 }
-EXPORT_SYMBOL(__xfrm_policy_destroy);
+EXPORT_SYMBOL(xfrm_policy_destroy);
 
 static void xfrm_policy_gc_kill(struct xfrm_policy *policy)
 {