xfrm: remove redundant parameter "int dir" in struct xfrm_mgr.acquire

Sematically speaking, xfrm_mgr.acquire is called when kernel intends to ask
user space IKE daemon to negotiate SAs with peers. IOW the direction will
*always* be XFRM_POLICY_OUT, so remove int dir for clarity.

Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 87cd0e4..7856c33 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1700,7 +1700,7 @@
 
 	read_lock(&xfrm_km_lock);
 	list_for_each_entry(km, &xfrm_km_list, list) {
-		acqret = km->acquire(x, t, pol, XFRM_POLICY_OUT);
+		acqret = km->acquire(x, t, pol);
 		if (!acqret)
 			err = acqret;
 	}