[ARM] 2866/1: add i.MX set_mctrl / get_mctrl functions

Patch from Sascha Hauer

This patch adds support for setting and getting RTS / CTS via
set_mtctrl / get_mctrl functions.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index d579761..74b80f7 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -830,7 +830,7 @@
 
 config SERIAL_TXX9
 	bool "TMPTX39XX/49XX SIO support"
-	depends HAS_TXX9_SERIAL
+	depends HAS_TXX9_SERIAL && BROKEN
 	select SERIAL_CORE
 	default y