serial: uartps: Fix kernel doc warnings

This patch fixes the kernel doc warnings in the driver.
Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/xilinx_uartps.c

@@ -186,6 +186,7 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
  * @pclk:		APB clock
  * @baud:		Current baud rate
  * @clk_rate_change_nb:	Notifier block for clock changes
+ * @quirks:		Flags for RXBS support.
  */
 struct cdns_uart {
 	struct uart_port	*port;