ppc4xx: Enable 440 GPIO init table CFG_440_GPIO_TABLE for 405 platforms

- Rename CFG_440_GPIO_TABLE to CFG_4xx_GPIO_TABLE
- Cleanup of the 4xx GPIO functions
- Move some GPIO defines from the cpu headers ppc405.h/ppc440.h into gpio.h

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/cpu/ppc4xx/cpu_init.c b/cpu/ppc4xx/cpu_init.c
index afb94cc..01ab523 100644
--- a/cpu/ppc4xx/cpu_init.c
+++ b/cpu/ppc4xx/cpu_init.c
@@ -112,7 +112,7 @@
 	unsigned long val;
 #endif
 
-#if defined(CONFIG_405EP) || defined (CONFIG_405EX)
+#if (defined(CONFIG_405EP) || defined (CONFIG_405EX)) && !defined(CFG_4xx_GPIO_TABLE)
 	/*
 	 * GPIO0 setup (select GPIO or alternate function)
 	 */
@@ -144,9 +144,9 @@
 #endif /* CONFIG_405EP */
 #endif /* CONFIG_405EP */
 
-#if defined(CFG_440_GPIO_TABLE)
+#if defined(CFG_4xx_GPIO_TABLE)
 	gpio_set_chip_configuration();
-#endif /* CFG_440_GPIO_TABLE */
+#endif /* CFG_4xx_GPIO_TABLE */
 
 	/*
 	 * External Bus Controller (EBC) Setup