[MINOR] fix the status return of the init script

R.I. Pienaar reported to me that the init script provided with
haproxy did not correctly report the status of the rhstatus()
function. In fact this was caused by the "exit $RETVAL" instead
of "exit $?" at the end.

examples/haproxy.init

@@ -108,7 +108,7 @@ case "$1" in
     ;;
   *)
     echo $"Usage: $BASENAME {start|stop|restart|reload|condrestart|status|check}"
-    RETVAL=1
+    exit 1
 esac
  
-exit $RETVAL
+exit $?