For abort() declaration.

Index: image/misc.c
--- image/misc.c.orig
+++ image/misc.c
@@ -12,7 +12,6 @@
 #include "xloadimage.h"
 #include "patchlevel"
 #include <signal.h>
-#include <stdlib.h>
 
 extern int      _Xdebug;
 extern Display *display;