Use broadcast address for slirp dhcp replies

Windows Vista drops unicast dhcp replies to its yet-unconfigured address,
so use a broadcast address.  This behaviour is allowed by the RFC.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6430 c046a42c-6fe2-441c-8c8c-71466251a162

slirp/bootp.c

@@ -191,6 +191,8 @@ static void bootp_reply(struct bootp_t *bp)
     rbp->bp_yiaddr = daddr.sin_addr; /* Client IP address */
     rbp->bp_siaddr = saddr.sin_addr; /* Server IP address */
 
+    daddr.sin_addr.s_addr = 0xffffffffu;
+
     q = rbp->bp_vend;
     memcpy(q, rfc1533_cookie, 4);
     q += 4;