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/hsdk_defconfig b/configs/hsdk_defconfig
index 943cd69..705ba6d 100644
--- a/configs/hsdk_defconfig
+++ b/configs/hsdk_defconfig
@@ -1,7 +1,7 @@
 CONFIG_ARC=y
 CONFIG_ISA_ARCV2=y
 CONFIG_TARGET_HSDK=y
-CONFIG_SYS_TEXT_BASE=0x81000000
+CONFIG_TEXT_BASE=0x81000000
 CONFIG_SYS_MALLOC_LEN=0x0200000
 CONFIG_SYS_MALLOC_F_LEN=0x400
 CONFIG_DM_GPIO=y