serial: imx: disable the receiver ready interrupt for imx_stop_rx

This patch disables the receiver ready interrupt for imx_stop_rx.
It reduces the interrupt numbers when the uart is going to close
or suspend.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/imx.c

@@ -439,6 +439,10 @@ static void imx_stop_rx(struct uart_port *port)
 
 	temp = readl(sport->port.membase + UCR2);
 	writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
+
+	/* disable the `Receiver Ready Interrrupt` */
+	temp = readl(sport->port.membase + UCR1);
+	writel(temp & ~UCR1_RRDYEN, sport->port.membase + UCR1);
 }
 
 /*