PaloAlto: hybrid address-group support

[sfraint]

PaloAlto allows hybrid address-group, where some constituent address may come from the vsys in which the address-group is defined and others may come from shared "vsys" (or presumably could also come from panorama).

For example, this config:

set deviceconfig system hostname address-group-hybrid
set shared address shared_addr ip-netmask 10.10.10.11
set address addr ip-netmask 10.10.10.10
set address-group group static [ addr shared_addr]

Should result in an address-group/IpSpace consisting of both 10.10.10.10 and 10.10.10.11, but instead results in an address-group only containing 10.10.10.10