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/comtrend_ct5361_ram_defconfig b/configs/comtrend_ct5361_ram_defconfig
index 608a888..e2f44d5 100644
--- a/configs/comtrend_ct5361_ram_defconfig
+++ b/configs/comtrend_ct5361_ram_defconfig
@@ -1,6 +1,6 @@
 CONFIG_MIPS=y
 CONFIG_SKIP_LOWLEVEL_INIT=y
-CONFIG_SYS_TEXT_BASE=0x80010000
+CONFIG_TEXT_BASE=0x80010000
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_ENV_SIZE=0x2000
 CONFIG_DM_GPIO=y