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/snow_defconfig b/configs/snow_defconfig
index 9c2292a..6921c56 100644
--- a/configs/snow_defconfig
+++ b/configs/snow_defconfig
@@ -5,7 +5,7 @@
 # CONFIG_SPL_USE_ARCH_MEMCPY is not set
 # CONFIG_SPL_USE_ARCH_MEMSET is not set
 CONFIG_ARCH_EXYNOS=y
-CONFIG_SYS_TEXT_BASE=0x43E00000
+CONFIG_TEXT_BASE=0x43E00000
 CONFIG_SYS_MALLOC_LEN=0x5004000
 CONFIG_SYS_MALLOC_F_LEN=0x400
 CONFIG_ARCH_EXYNOS5=y