net pkgen.c:fix no need for check

vfree() does its own 'NULL' check, so no need for check before
calling it.

Signed-off-by: Figo.zhang <figo1802@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index b8ccd3c..19b8c20 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3691,8 +3691,7 @@
 #ifdef CONFIG_XFRM
 	free_SAs(pkt_dev);
 #endif
-	if (pkt_dev->flows)
-		vfree(pkt_dev->flows);
+	vfree(pkt_dev->flows);
 	kfree(pkt_dev);
 	return err;
 }
@@ -3791,8 +3790,7 @@
 #ifdef CONFIG_XFRM
 	free_SAs(pkt_dev);
 #endif
-	if (pkt_dev->flows)
-		vfree(pkt_dev->flows);
+	vfree(pkt_dev->flows);
 	kfree(pkt_dev);
 	return 0;
 }