XXX push upstream

Index: configure
--- configure.orig
+++ configure
@@ -15429,7 +15429,7 @@ printf %s "checking for I4B... " >&6; }
 #include <net/netisr.h>
 #include <net/route.h>
 
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__FreeBSD_kernel__)
+#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
 #include <net/if_sppp.h>
 #else
 #include <i4b/sppp/if_sppp.h>
@@ -15476,7 +15476,7 @@ printf %s "checking for I4B accounting... " >&6; }
 #include <net/netisr.h>
 #include <net/route.h>
 
-#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__FreeBSD_kernel__)
+#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
 #include <net/if_sppp.h>
 #else
 #include <i4b/sppp/if_sppp.h>
