DynamicTablesPkg: AcpiSsdtPcieLibArm: Allow use of segment number as UID

DynamicTablesPkg: AcpiSsdtPcieLibArm: Allow use of segment number as UID

Add support for selecting to use index or segment number as UID and name.
This allows the path of the nodes to be well known.
For example, if the PCIe node needs to be notified from by an interrupt
for a Generic Event Device

Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>