ppc4xx: Use common NS16550 driver for PPC4xx UART

This patch removes the PPC4xx UART driver. Instead the common NS16550
driver is used, since all PPC4xx SoC's use this peripheral device.

The file 4xx_uart.c now only implements the UART clock calculation
function which also sets the SoC internal UART divisors.

All PPC4xx board config headers are changed to use this common NS16550
driver now.

Tested on these boards:
acadia, canyonlands, katmai, kilauea, sequoia, zeus

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/include/configs/JSE.h b/include/configs/JSE.h
index 98f5661a..c692b54 100644
--- a/include/configs/JSE.h
+++ b/include/configs/JSE.h
@@ -95,9 +95,13 @@
 #define CONFIG_ENV_OFFSET	0x00
 #define CONFIG_ENV_SIZE	512
 
-
   /* The JSE connects UART1 to the console tap connector. */
-#define CONFIG_UART1_CONSOLE	1
+#define CONFIG_CONS_INDEX	2
+#define CONFIG_SYS_NS16550
+#define CONFIG_SYS_NS16550_SERIAL
+#define CONFIG_SYS_NS16550_REG_SIZE	1
+#define CONFIG_SYS_NS16550_CLK		get_serial_clock()
+
   /* Set console baudrate to 9600 */
 #define CONFIG_BAUDRATE		9600