srogue: fix an uninitialized variable.

In wanderer(), if rp == hr, the loop could test ch before its value has
been set.  Initializing ch to '-' now causes the loop to repeat until
a location is found.

srogue/monsters.c

@@ -193,7 +193,7 @@ char type;
  */
 wanderer()
 {
-	reg int ch;
+	reg int ch = '-';
 	reg struct room *rp, *hr = player.t_room;
 	reg struct linked_list *item;
 	reg struct thing *tp;