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/netstar/config.mk b/board/netstar/config.mk
index 8b73e97..9e1446e 100644
--- a/board/netstar/config.mk
+++ b/board/netstar/config.mk
@@ -3,9 +3,9 @@
 # entry 1000'8000 (mem base + reserved)
 #
 # We load ourself to internal RAM at 2001'2000
-# Check map file when changing TEXT_BASE.
+# Check map file when changing CONFIG_SYS_TEXT_BASE.
 # Everything has fit into 192kB internal SRAM!
 #
 
-# XXX TEXT_BASE = 0x20012000
-TEXT_BASE = 0x13FC0000
+# XXX CONFIG_SYS_TEXT_BASE = 0x20012000
+CONFIG_SYS_TEXT_BASE = 0x13FC0000