serial: uartlite: Add uartlite to Kconfig

- Move config option out of board file.
- Remove uartlite address from config file

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Thomas Chou <thomas@wytron.com.tw>

drivers/serial/Kconfig

@@ -278,4 +278,11 @@ config UNIPHIER_SERIAL
 	  If you have a UniPhier based board and want to use the on-chip
 	  serial ports, say Y to this option. If unsure, say N.
 
+config XILINX_UARTLITE
+	bool "Xilinx Uarlite support"
+	depends on DM_SERIAL && (MICROBLAZE || ARCH_ZYNQ || ARCH_ZYNQMP)
+	help
+	  If you have a Xilinx based board and want to use the uartlite
+	  serial ports, say Y to this option. If unsure, say N.
+
 endmenu