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/purple/purple.c b/board/purple/purple.c
index 54bef65..4e9e700 100644
--- a/board/purple/purple.c
+++ b/board/purple/purple.c
@@ -222,10 +222,10 @@
 	FUNCPTR absEntry;
 	ulong *src,*dst;
 
-	src = (ulong *)(TEXT_BASE + 0x428);
+	src = (ulong *)(CONFIG_SYS_TEXT_BASE + 0x428);
 	dst = (ulong *)0xbf0081d0;
 
-	absEntry = (FUNCPTR)(TEXT_BASE + 0x400);
+	absEntry = (FUNCPTR)(CONFIG_SYS_TEXT_BASE + 0x400);
 	absEntry(src,dst,0x6);
 
 	src = (ulong *)((ulong)copydwords & 0xfffffff8);