Possum's llist uses memcpy, so include string.h and eliminate a warning.

git-svn-id: svn://svn.code.sf.net/p/bitchx/code/trunk@322 13b04d17-f746-0410-82c6-800466cd88b0

dll/possum/llist.c

@@ -1,4 +1,5 @@
 #include <stdlib.h>
+#include <string.h>
 #include "llist.h"
 
 llist *lmake(size_t size) {