slirp: Fix type casts and format strings in debug code

Casting pointers to long won't work on 64 bit Windows.
It is not needed with the right format strings.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Jason Wang <jasowang@redhat.com>
diff --git a/slirp/ip_icmp.c b/slirp/ip_icmp.c
index 9f1cb08..23b9f0f 100644
--- a/slirp/ip_icmp.c
+++ b/slirp/ip_icmp.c
@@ -125,7 +125,7 @@
   Slirp *slirp = m->slirp;
 
   DEBUG_CALL("icmp_input");
-  DEBUG_ARG("m = %lx", (long )m);
+  DEBUG_ARG("m = %p", m);
   DEBUG_ARG("m_len = %d", m->m_len);
 
   /*
@@ -252,7 +252,7 @@
   register struct mbuf *m;
 
   DEBUG_CALL("icmp_error");
-  DEBUG_ARG("msrc = %lx", (long )msrc);
+  DEBUG_ARG("msrc = %p", msrc);
   DEBUG_ARG("msrc_len = %d", msrc->m_len);
 
   if(type!=ICMP_UNREACH && type!=ICMP_TIMXCEED) goto end_error;