armv8: ls1028ardb: Add support for LS1028ARDB

LS1028A is an ARMv8 implementation. LS1028ARDB is an evaluation
platform that supports the LS1028A family SoCs. This patch add basic
support of the platform.

Signed-off-by: Sudhanshu Gupta <sudhanshu.gupta@nxp.com>
Signed-off-by: Rai Harninder <harninder.rai@nxp.com>
Signed-off-by: Rajesh Bhagat <rajesh.bhagat@nxp.com>
Signed-off-by: Bhaskar Upadhaya <Bhaskar.Upadhaya@nxp.com>
Signed-off-by: Tang Yuantian <andy.tang@nxp.com>
Signed-off-by: Prabhakar Kushwaha <prabhakar.kushwaha@nxp.com>