tty: serial: Add driver for MEN's 16z135 High Speed UART.

Add driver for MEN's 16z135 High Speed UART.

The 16z135 is a memory mapped UART Core on an MCB FPGA and has 1024 byte
deep FIFO buffers for the RX and TX path. It also has configurable FIFO
fill level IRQs and data copied to and from the hardware has to be
acknowledged.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@men.de>
Reviewed-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 396cf84..30530e4 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1509,6 +1509,16 @@
 	depends on SERIAL_ST_ASC=y
 	select SERIAL_CORE_CONSOLE
 
+config SERIAL_MEN_Z135
+	tristate "MEN 16z135 Support"
+	depends on MCB
+	help
+	  Say yes here to enable support for the MEN 16z135 High Speed UART IP-Core
+	  on a MCB carrier.
+
+	  This driver can also be build as a module. If so, the module will be called
+	  men_z135_uart.ko
+
 endmenu
 
 endif # TTY