ppc4xx: Consolidate pci_pre_init() function

This patch removes the duplicted implementations of the pci_pre_init()
function by introducing a weak default function for it. This weak default
has a different implementation for some PPC variants. It can be
overridden by a board specific version.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/include/configs/PMC440.h b/include/configs/PMC440.h
index d2c5188..ac5584c 100644
--- a/include/configs/PMC440.h
+++ b/include/configs/PMC440.h
@@ -435,6 +435,7 @@
 /* Board-specific PCI */
 #define CONFIG_SYS_PCI_TARGET_INIT
 #define CONFIG_SYS_PCI_MASTER_INIT
+#define CONFIG_SYS_PCI_BOARD_FIXUP_IRQ
 
 /* PCI identification */
 #define CONFIG_SYS_PCI_SUBSYS_VENDORID 0x12FE	/* PCI Vendor ID: esd gmbh      */
diff --git a/include/configs/korat.h b/include/configs/korat.h
index 7e74ef7..026dd08 100644
--- a/include/configs/korat.h
+++ b/include/configs/korat.h
@@ -360,6 +360,7 @@
 /* Board-specific PCI */
 #define CONFIG_SYS_PCI_TARGET_INIT
 #define CONFIG_SYS_PCI_MASTER_INIT
+#define CONFIG_SYS_PCI_BOARD_FIXUP_IRQ
 
 #define CONFIG_SYS_PCI_SUBSYS_VENDORID 0x10e8	/* AMCC				*/
 #define CONFIG_SYS_PCI_SUBSYS_ID       0xcafe	/* Whatever			*/
diff --git a/include/configs/sequoia.h b/include/configs/sequoia.h
index 9605ce2..5788d58 100644
--- a/include/configs/sequoia.h
+++ b/include/configs/sequoia.h
@@ -364,6 +364,7 @@
 /* Board-specific PCI */
 #define CONFIG_SYS_PCI_TARGET_INIT
 #define CONFIG_SYS_PCI_MASTER_INIT
+#define CONFIG_SYS_PCI_BOARD_FIXUP_IRQ
 
 #define CONFIG_SYS_PCI_SUBSYS_VENDORID 0x10e8	/* AMCC				*/
 #define CONFIG_SYS_PCI_SUBSYS_ID       0xcafe	/* Whatever			*/