ospfd: Forward reference ospf area config

ospfd: Forward reference ospf area config

Upon restart frr interface configuration applied
prior to 'router ospf' configuration. 'ip ospf area x'
config fails if ospf instance is not active.

Allow 'ip ospf area x' configuration to allow in absence
of ospf instance. Upon 'router ospf' walk through vrf
aware interfaces, active area cofigurations.
When vrf is enabled, router-id update also walk through
vrf aware interfaces to enable area configuration
via network_run_interface.

Ticket: CM-18927
Reviewed By:
Testing Done:
Configured multiple interfaces with 'ip ospf area x'
with multiple areas/interface combinations.
Upon router ospf enable along with vrf is active,
interfaces comes up in respective area, ospf neighborship
comes up fine.

Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>