undefine ifa_dstaddr in case it has been defined to be something else

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@9344 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/roken/ifaddrs.hin

@@ -36,6 +36,13 @@
 #ifndef __ifaddrs_h__
 #define __ifaddrs_h__
 
+/*
+ * the interface is defined in terms of the fields below, and this is
+ * sometimes #define'd, so there seems to be no simple way of solving
+ * this and this seemed the best. */
+
+#undef ifa_dstaddr
+
 struct ifaddrs {
     struct ifaddrs *ifa_next;
     char *ifa_name;