arch: arm: Agilex5 enablement

This patch is to enable Agilex5 platform for Intel
product. Changes, modification and new files are
created for board, dts, configs and makefile to
create the base for Agilex5.

Signed-off-by: Jit Loon Lim <jit.loon.lim@intel.com>
Reviewed-by: Tien Fong Chee <tien.fong.chee@intel.com>