qpkg/jrb.c: removed unnecessary inclusion of ctype.h and string.h

qpkg/jrb.c

@@ -40,10 +40,8 @@ Fax: 865-974-4404
 /* modified for THINK C 6.0 for Macintosh by Chris Bartley */
 /* Heavily edited and reformatted to K&R style 2010 by Werner Almesberger */
 
-#include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <ctype.h>
 #include "jrb.h"