net: xfrm: drop check of pols[0] for the second time

!pols[0] is checked earlier.  If we don't return, pols[0] is always
true.  We should drop the check of pols[0] for the second time and the
binary is also smaller.

Before:
   text	   data	    bss	    dec	    hex	filename
  48395	    957	    240	  49592	   c1b8	net/xfrm/xfrm_policy.o

After:
   text	   data	    bss	    dec	    hex	filename
  48379	    957	    240	  49576	   c1a8	net/xfrm/xfrm_policy.o
Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

net/xfrm/xfrm_policy.c

@@ -2680,7 +2680,7 @@ static int xfrm_expand_policies(const struct flowi *fl, u16 family,
 	*num_xfrms = pols[0]->xfrm_nr;
 
 #ifdef CONFIG_XFRM_SUB_POLICY
-	if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
+	if (pols[0]->action == XFRM_POLICY_ALLOW &&
 	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
 		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
 						    XFRM_POLICY_TYPE_MAIN,