DynamicTablesPkg: FdtHwInfoParser: Add GIC dispatcher

The GIC Dispatcher is the top-level component that is responsible
for invoking the respective parsers for GICC, GICD, GIC MSI Frame,
GIC ITS and the GICR.

Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>