Rename CONFIG_SYS_TEXT_BASE to CONFIG_TEXT_BASE

The current name is inconsistent with SPL which uses CONFIG_SPL_TEXT_BASE
and this makes it imposible to use CONFIG_VAL().

Rename it to resolve this problem.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/configs/siemens-am33x-common.h b/include/configs/siemens-am33x-common.h
index fcb0fd5..5759794 100644
--- a/include/configs/siemens-am33x-common.h
+++ b/include/configs/siemens-am33x-common.h
@@ -63,7 +63,7 @@
 #define	CONFIG_SYS_NAND_ECCTOTAL	(CONFIG_SYS_NAND_ECCBYTES * \
 						CONFIG_SYS_NAND_ECCSTEPS)
 
-#define	CONFIG_SYS_NAND_U_BOOT_START	CONFIG_SYS_TEXT_BASE
+#define	CONFIG_SYS_NAND_U_BOOT_START	CONFIG_TEXT_BASE
 
 /*
  * 1MB into the SDRAM to allow for SPL's bss at the beginning of SDRAM