ARM: zynq: Move CONFIG_SYS_TEXT_BASE to Kconfig

Enable CONFIG_SYS_TEXT_BASE via Kconfig.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/configs/zynq_zc770_xm012_defconfig b/configs/zynq_zc770_xm012_defconfig
index 8e80a90..c01faaa 100644
--- a/configs/zynq_zc770_xm012_defconfig
+++ b/configs/zynq_zc770_xm012_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_ARCH_ZYNQ=y
 # CONFIG_MMC is not set
+CONFIG_SYS_TEXT_BASE=0x4000000
 CONFIG_DEFAULT_DEVICE_TREE="zynq-zc770-xm012"
 CONFIG_FIT=y
 CONFIG_FIT_VERBOSE=y