Rename netdev_*route to end in route4

Functions for IPv6 will be added soon afterwards. Also take the chance
to check for address length in sgsnemu and only apply the route if the
address matches.

Change-Id: Ic6c1b3c11c56f047e6e8c6f1040257fd62afea0f
diff --git a/lib/netdev.h b/lib/netdev.h
index 74c42da..5dab27f 100644
--- a/lib/netdev.h
+++ b/lib/netdev.h
@@ -65,8 +65,8 @@
 extern int netdev_addaddr6(const char *devname, struct in6_addr *addr,
 			   struct in6_addr *dstaddr, int prefixlen);
 
-extern int netdev_addroute(struct in_addr *dst, struct in_addr *gateway, struct in_addr *mask);
-extern int netdev_delroute(struct in_addr *dst, struct in_addr *gateway, struct in_addr *mask);
+extern int netdev_addroute4(struct in_addr *dst, struct in_addr *gateway, struct in_addr *mask);
+extern int netdev_delroute4(struct in_addr *dst, struct in_addr *gateway, struct in_addr *mask);
 
 extern int netdev_ip_local_get(const char *devname, struct in46_prefix *prefix_list,
 				size_t prefix_size, int flags);