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/k2e_evm_defconfig b/configs/k2e_evm_defconfig
index ed2affd..977348e 100644
--- a/configs/k2e_evm_defconfig
+++ b/configs/k2e_evm_defconfig
@@ -4,7 +4,7 @@
 CONFIG_SYS_DCACHE_OFF=y
 CONFIG_ARCH_CPU_INIT=y
 CONFIG_ARCH_KEYSTONE=y
-CONFIG_SYS_TEXT_BASE=0xC000000
+CONFIG_TEXT_BASE=0xC000000
 CONFIG_SYS_MALLOC_LEN=0x2000000
 CONFIG_SYS_MALLOC_F_LEN=0x400
 CONFIG_TI_COMMON_CMD_OPTIONS=y