arm64: dts: add LX2160AQDS board support

The LX2160A QorIQ Development System (QDS) is a test, evaluation, and
development platform, supporting QorIQ LX2160A processor.

Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Signed-off-by: Pankaj Bansal <pankaj.bansal@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>