serial: imx: Fix build breakage

Fix breakage introduced by
commit c557d392fbf5badd693ea1946a4317c87a26a716,
'serial: Test for no tx data on tx restart'.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/imx.c

@@ -567,7 +567,7 @@ static void imx_start_tx(struct uart_port *port)
 	struct imx_port *sport = (struct imx_port *)port;
 	unsigned long temp;
 
-	if (uart_circ_empty(&port.state->xmit))
+	if (uart_circ_empty(&port->state->xmit))
 		return;
 
 	if (USE_IRDA(sport)) {