[ARM] 21285 serial: fix build error

drivers/serial/21285.c: In function 'serial21285_set_termios':
drivers/serial/21285.c:280: error: 'tty' undeclared (first use in this function)
drivers/serial/21285.c:280: error: (Each undeclared identifier is reported only once
drivers/serial/21285.c:280: error: for each function it appears in.)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/serial/21285.c b/drivers/serial/21285.c
index 6a48dfa..0276471 100644
--- a/drivers/serial/21285.c
+++ b/drivers/serial/21285.c
@@ -237,6 +237,12 @@
 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); 
 	quot = uart_get_divisor(port, baud);
 
+	if (port->info && port->info->tty) {
+		struct tty_struct *tty = port->info->tty;
+		unsigned int b = port->uartclk / (16 * quot);
+		tty_encode_baud_rate(tty, b, b);
+	}
+
 	switch (termios->c_cflag & CSIZE) {
 	case CS5:
 		h_lcr = 0x00;
@@ -277,8 +283,6 @@
 	if (termios->c_iflag & INPCK)
 		port->read_status_mask |= RXSTAT_FRAME | RXSTAT_PARITY;
 
-	tty_encode_baud_rate(tty,  baud, baud);
-
 	/*
 	 * Which character status flags should we ignore?
 	 */