ospfd: fix crash no router ospf/show running

ospfd: fix crash no router ospf/show running

no router ospf removes default ospf instance,
if there are other non-default vrf instance present
with interface level configuration. Lookup ospf instance
for ifp->vrf_id, if ospf instnace present use that
   to access 'instance id'.

Ticket: CM-19078
Testing Done:
run no router ospf and show running config along with other
non-default vrf aware ospf configurations.

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