configs: Layerscape: Remove the 'fdt_addr' env

On Layerscape platforms, the DTB is loaded from boot filesystem,
per the fdt_addr description in doc/README.distro, it must be
removed.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
[Rebased]
Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>
14 files changed