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/xilinx_zynq_virt_defconfig b/configs/xilinx_zynq_virt_defconfig
index c12a1cb..1b4aa85 100644
--- a/configs/xilinx_zynq_virt_defconfig
+++ b/configs/xilinx_zynq_virt_defconfig
@@ -2,7 +2,7 @@
 CONFIG_SPL_SYS_DCACHE_OFF=y
 CONFIG_SYS_L2CACHE_OFF=y
 CONFIG_ARCH_ZYNQ=y
-CONFIG_SYS_TEXT_BASE=0x4000000
+CONFIG_TEXT_BASE=0x4000000
 CONFIG_ENV_OFFSET=0xE00000
 CONFIG_DM_GPIO=y
 CONFIG_DEFAULT_DEVICE_TREE="zynq-zc706"