Revert commit 8e706c4d0dab214c625a2df84a0ca69a76bae65d in linux-2.6:
  avr32: add hardware handshake support to atmel_serial

Reverting commit since it breaks hardware flow control for at91sam9g20

diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c
index 9d948bc..b659f2c 100644
--- a/drivers/serial/atmel_serial.c
+++ b/drivers/serial/atmel_serial.c
@@ -1020,8 +1020,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 
 	/* Get current mode register */
 	mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL
-					| ATMEL_US_NBSTOP | ATMEL_US_PAR
-					| ATMEL_US_USMODE);
+					| ATMEL_US_NBSTOP | ATMEL_US_PAR);
 
 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
 	quot = uart_get_divisor(port, baud);
@@ -1066,12 +1065,6 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 	} else
 		mode |= ATMEL_US_PAR_NONE;
 
-	/* hardware handshake (RTS/CTS) */
-	if (termios->c_cflag & CRTSCTS)
-		mode |= ATMEL_US_USMODE_HWHS;
-	else
-		mode |= ATMEL_US_USMODE_NORMAL;
-
 	spin_lock_irqsave(&port->lock, flags);
 
 	port->read_status_mask = ATMEL_US_OVRE;