VXLAN: further unify ip4/ip6 ctl plane handling

fix wrong udp error codes in decap ip6 handling

Change-Id: Ibf791a995128d38b31725c1ee67ec9d1c9dffca2
Signed-off-by: Eyal Bari <ebari@cisco.com>
diff --git a/src/vnet/vxlan/decap.c b/src/vnet/vxlan/decap.c
index d5a9442..514b2c9 100644
--- a/src/vnet/vxlan/decap.c
+++ b/src/vnet/vxlan/decap.c
@@ -1032,8 +1032,8 @@
 	    }
 	  else
 	    {
-	      error1 = good_udp1 ? 0 : IP4_ERROR_UDP_CHECKSUM;
-	      error1 = (len_diff1 >= 0) ? error1 : IP4_ERROR_UDP_LENGTH;
+	      error1 = good_udp1 ? 0 : IP6_ERROR_UDP_CHECKSUM;
+	      error1 = (len_diff1 >= 0) ? error1 : IP6_ERROR_UDP_LENGTH;
 	    }
 
 	  next1 = error1 ?