tty: xilinx_uartps: Update copyright text to correct format

Based on recommended guidance Copyright term should be also present in
front of (c). That's why aligned drivers to match this pattern.
It helps automated tools with source code scanning.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/20220729114748.18332-3-shubhrajyoti.datta@xilinx.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/xilinx_uartps.c

@@ -2,7 +2,7 @@
 /*
  * Cadence UART driver (found in Xilinx Zynq)
  *
- * 2011 - 2014 (C) Xilinx Inc.
+ * Copyright (c) 2011 - 2014 Xilinx, Inc.
  *
  * This driver has originally been pushed by Xilinx using a Zynq-branding. This
  * still shows in the naming of this file, the kconfig symbols and some symbols