serial: xilinx_uartps: remove superfluous IDR write

The datesheet clearly states, that writing low bits to the
XUARTPS_IDR register have no effect. Remove the write.
Signed-off-by: NSteffen Trumtrar <s.trumtrar@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/xilinx_uartps.c

@@ -583,9 +583,6 @@ static int xuartps_startup(struct uart_port *port)
 	xuartps_writel(XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_PARITY |
 		XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN |
 		XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT, XUARTPS_IER_OFFSET);
-	xuartps_writel(~(XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_PARITY |
-		XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN |
-		XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT), XUARTPS_IDR_OFFSET);
 
 	return retval;
 }