ppc4xx: Prepare Bamboo port for NAND booting support

This patch updates the "normal" Bamboo NOR booting port, so
that it is compatible with the coming soon NAND booting
Bamboo port.

It also enables the 2nd NAND flash on the Bamboo.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/amcc/bamboo/config.mk b/board/amcc/bamboo/config.mk
index 9d7f4c3..b46527d 100644
--- a/board/amcc/bamboo/config.mk
+++ b/board/amcc/bamboo/config.mk
@@ -1,5 +1,5 @@
 #
-# (C) Copyright 2002-2006
+# (C) Copyright 2002-2007
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 #
 # See file CREDITS for list of people who contributed to this
@@ -21,7 +21,11 @@
 # MA 02111-1307 USA
 #
 
+sinclude $(OBJTREE)/board/$(BOARDDIR)/config.tmp
+
+ifndef TEXT_BASE
 TEXT_BASE = 0xFFFA0000
+endif
 
 PLATFORM_CPPFLAGS += -DCONFIG_440=1