(TTYget): use unsigned char to make sure a positive number is returned

when successful


git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@14819 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/editline/editline.c

@@ -179,7 +179,7 @@ TTYstring(unsigned char *p)
 static int
 TTYget()
 {
-    char c;
+    unsigned char c;
     int e;
 
     TTYflush();