arm64: dts: agilex5: add initial support for Intel Agilex5 SoCFPGA

Add the initial device tree files for Intel Agilex5 SoCFPGA platform.

Reviewed-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>