IPv6 support for user IP

This patch enables the use of IPv6 PDP contexts.  The phone will
have to request an IPv6 End-user-Address, and the GGSN will have
to be configured for an IPv6 pool.

The outer transport-layer IP between SGSN and GGSN must still be
IPv4, it is not modified by this patch

Change-Id: I22c3bf32a98e5daf99d6eaeac8c9f95cc7574774
diff --git a/sgsnemu/sgsnemu.c b/sgsnemu/sgsnemu.c
index af8f9fa..8c9cfd3 100644
--- a/sgsnemu/sgsnemu.c
+++ b/sgsnemu/sgsnemu.c
@@ -1329,7 +1329,7 @@
 		return EOF;	/* Not what we expected */
 	}
 
-	if (pdp_euaton(&pdp->eua, &addr.v4)) {
+	if (in46a_from_eua(&pdp->eua, &addr)) {
 		printf
 		    ("Received create PDP context response. Cause value: %d\n",
 		     cause);