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/configs/T2080RDB_SDCARD_defconfig b/configs/T2080RDB_SDCARD_defconfig
index cc26ade..46e603b 100644
--- a/configs/T2080RDB_SDCARD_defconfig
+++ b/configs/T2080RDB_SDCARD_defconfig
@@ -1,5 +1,5 @@
 CONFIG_PPC=y
-CONFIG_SYS_TEXT_BASE=0x00200000
+CONFIG_TEXT_BASE=0x00200000
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_ENV_SIZE=0x2000