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/espresso7420_defconfig b/configs/espresso7420_defconfig
index f884102..a003f85 100644
--- a/configs/espresso7420_defconfig
+++ b/configs/espresso7420_defconfig
@@ -1,7 +1,7 @@
 CONFIG_ARM=y
 CONFIG_ARCH_CPU_INIT=y
 CONFIG_ARCH_EXYNOS=y
-CONFIG_SYS_TEXT_BASE=0x43E00000
+CONFIG_TEXT_BASE=0x43E00000
 CONFIG_SYS_MALLOC_LEN=0x5004000
 CONFIG_ARCH_EXYNOS7=y
 CONFIG_NR_DRAM_BANKS=8