Mainline BSP switches from using imx-boot package, which provides the
boot container for mx8 derivatives, to the boot container provided as a
part of u-boot package and usage of imx-boot-container class.
Drop the compatibility with mainline BSP from the recipe, and let
derivatives that are built with it to integrate support of new boot
container mechanism.
Fixes: 6fc0971c ("imx-mkimage: allow to be used with mainline bsp for mx8m)" Signed-off-by: Andrey Zhizhikin <andrey.z@gmail.com>
