SERIAL: omap: allow hardware assisted rts/cts modes to be disabled

There is nothing which clears the auto RTS/CTS bits, so once hardware
flow control gets enabled, there's no possibility to disable it.
So, clear these bits when CRTSCTS is cleared.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 6d3d26a..b6a1925 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -921,6 +921,13 @@
 		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 		serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
 		serial_out(up, UART_LCR, cval);
+	} else {
+		/* Disable AUTORTS and AUTOCTS */
+		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
+
+		serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+		serial_out(up, UART_EFR, up->efr);
+		serial_out(up, UART_LCR, cval);
 	}
 
 	serial_omap_set_mctrl(&up->port, up->port.mctrl);