imx: hab: rework secure boot support for imx6

Rework secure boot support for imx6, move existing hab support
for imx6 into imx-common for SoC reuse.

Signed-off-by: Adrian Alonso <aalonso@freescale.com>
diff --git a/arch/arm/imx-common/Makefile b/arch/arm/imx-common/Makefile
index 1698d06..4abffee 100644
--- a/arch/arm/imx-common/Makefile
+++ b/arch/arm/imx-common/Makefile
@@ -27,6 +27,7 @@
 obj-y 	+= cache.o init.o
 obj-$(CONFIG_CMD_SATA) += sata.o
 obj-$(CONFIG_IMX_VIDEO_SKIP) += video.o
+obj-$(CONFIG_SECURE_BOOT)    += hab.o
 endif
 ifeq ($(SOC),$(filter $(SOC),vf610))
 obj-y += ddrmc-vf610.o