*: use void * for printing pointers

On higher warning levels, compilers expect %p printf arguments to be
void *.  Since format string / argument warnings can be useful
otherwise, let's get rid of this noise by sprinkling casts to void *
over printf calls.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/ospf6d/ospf6_lsa.c b/ospf6d/ospf6_lsa.c
index 8eeb995..b4348f4 100644
--- a/ospf6d/ospf6_lsa.c
+++ b/ospf6d/ospf6_lsa.c
@@ -494,7 +494,7 @@
   vty_out (vty, "Lock: %d %s", lsa->lock, VNL);
   vty_out (vty, "ReTx Count: %d%s", lsa->retrans_count, VNL);
   vty_out (vty, "Threads: Expire: 0x%p, Refresh: 0x%p %s",
-	   lsa->expire, lsa->refresh, VNL);
+           (void *)lsa->expire, (void *)lsa->refresh, VNL);
   vty_out (vty, "%s", VNL);
   return;
 }