Rename TEXT_BASE into CONFIG_SYS_TEXT_BASE

The change is currently needed to be able to remove the board
configuration scripting from the top level Makefile and replace it by
a simple, table driven script.

Moving this configuration setting into the "CONFIG_*" name space is
also desirable because it is needed if we ever should move forward to
a Kconfig driven configuration system.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/board/ids8247/config.mk b/board/ids8247/config.mk
index 2a7f3dd..1aee97c 100644
--- a/board/ids8247/config.mk
+++ b/board/ids8247/config.mk
@@ -29,6 +29,7 @@
 # for the "final" configuration, with U-Boot in flash, or the address
 # in RAM where U-Boot is loaded at for debugging.
 #
-TEXT_BASE = 0xfff00000
+CONFIG_SYS_TEXT_BASE = 0xfff00000
 
-PLATFORM_CPPFLAGS += -DTEXT_BASE=$(TEXT_BASE) -I$(TOPDIR)
+PLATFORM_CPPFLAGS += -DCONFIG_SYS_TEXT_BASE=$(CONFIG_SYS_TEXT_BASE) \
+	-I$(TOPDIR)