Fix dlls/iphlpapi/ipstats.c build

[Gerald Pfeifer]

The latest update here broke the build on FreeBSD 6.2 in a number of
ways; this is the first fix.

Gerald @FreeBSD.org

ChangeLog:
#include <netinet/in_systm.h> if present.

Index: dlls/iphlpapi/ipstats.c
===================================================================
RCS file: /home/wine/wine/dlls/iphlpapi/ipstats.c,v
retrieving revision 1.35
diff -u -3 -p -r1.35 ipstats.c
--- dlls/iphlpapi/ipstats.c	26 Jun 2008 11:49:10 -0000	1.35
+++ dlls/iphlpapi/ipstats.c	27 Jun 2008 11:04:09 -0000
@@ -77,6 +77,9 @@
 #ifdef HAVE_NETINET_TCP_TIMER_H
 #include <netinet/tcp_timer.h>
 #endif
+#ifdef HAVE_NETINET_IN_SYSTM_H
+#include <netinet/in_systm.h>
+#endif
 #ifdef HAVE_NETINET_IP_ICMP_H
 #include <netinet/ip_icmp.h>
 #endif