xfree86: fix not reached code in tty code

CLEARRTS_SUPPORT cannot be triggered at all. Notice that mouse driver manual
page states the support for it though.

Signed-off-by: Tiago Vignatti <tiago.vignatti@nokia.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

hw/xfree86/os-support/shared/posix_tty.c

@@ -340,14 +340,9 @@ xf86SetSerial (int fd, pointer options)
 
 	if ((xf86SetBoolOption (options, "ClearRTS", FALSE)))
 	{
-#ifdef CLEARRTS_SUPPORT
-		val = TIOCM_RTS;
-		SYSCALL (ioctl(fd, TIOCMBIC, &val));
-#else
 		xf86Msg (X_WARNING,
 			 "Option ClearRTS not supported on this OS\n");
 			return (-1);
-#endif
 		xf86MarkOptionUsedByName (options, "ClearRTS");
 	}