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/elgin-rv1108_defconfig b/configs/elgin-rv1108_defconfig
index adfc56c..a3a96f9 100644
--- a/configs/elgin-rv1108_defconfig
+++ b/configs/elgin-rv1108_defconfig
@@ -1,7 +1,7 @@
 CONFIG_ARM=y
 CONFIG_SKIP_LOWLEVEL_INIT=y
 CONFIG_ARCH_ROCKCHIP=y
-CONFIG_SYS_TEXT_BASE=0x60000000
+CONFIG_TEXT_BASE=0x60000000
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_ENV_OFFSET=0x3F8000
 CONFIG_DEFAULT_DEVICE_TREE="rv1108-elgin-r1"