imx8: save args passed from ATF

We use information from ATF to know whether OP-TEE is running or not.
So save args passed from ATF.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/mach-imx/imx8/Makefile b/arch/arm/mach-imx/imx8/Makefile
index 7fc3476..97f9d22 100644
--- a/arch/arm/mach-imx/imx8/Makefile
+++ b/arch/arm/mach-imx/imx8/Makefile
@@ -4,7 +4,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-y += cpu.o iomux.o misc.o
+obj-y += cpu.o iomux.o misc.o lowlevel_init.o
 obj-$(CONFIG_OF_SYSTEM_SETUP) += fdt.o
 
 ifdef CONFIG_SPL_BUILD