tty: xuartps: Rebrand driver as Cadence UART

Zynq's UART is Cadence IP. Make this visible in the prompt in kconfig
and additional comments in the driver.
This also renames functions and symbols, as far as possible without
breaking user space API, to reflect the Cadence origin. This is achieved
through simple search and replace:
 - s/XUARTPS/CDNS_UART/g
 - s/xuartps/cdns_uart/g
The only exceptions are PORT_XUARTPS and the driver name, which stay as is,
due to their exposure to user space. As well as the - no legacy -
compatibility string 'xlnx,xuartps'

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/Kconfig

@@ -1369,18 +1369,19 @@ config SERIAL_MXS_AUART_CONSOLE
 	  Enable a MXS AUART port to be the system console.
 
 config SERIAL_XILINX_PS_UART
-	tristate "Xilinx PS UART support"
+	tristate "Cadence (Xilinx Zynq) UART support"
 	depends on OF
 	select SERIAL_CORE
 	help
-	  This driver supports the Xilinx PS UART port.
+	  This driver supports the Cadence UART. It is found e.g. in Xilinx
+	  Zynq.
 
 config SERIAL_XILINX_PS_UART_CONSOLE
-	bool "Xilinx PS UART console support"
+	bool "Cadence UART console support"
 	depends on SERIAL_XILINX_PS_UART=y
 	select SERIAL_CORE_CONSOLE
 	help
-	  Enable a Xilinx PS UART port to be the system console.
+	  Enable a Cadence UART port to be the system console.
 
 config SERIAL_AR933X
 	tristate "AR933X serial port support"