ospf6d: stop looping thru same Inter-Area Router LSAs

ospf6d: stop looping thru same Inter-Area Router LSAs

Processing loop uncovered when there are multiple ABRs also
acting as ASBRs into the same area in ospf6.  The problem
was that when looking thru the list of Inter-area router
entries, if the current entry being processed matched, it
still merged next-hops and re-initiated the process.  In
this fix, if the route/path matches and the next-hops also
match, there is no need to re-initiate the examine process.

Ticket: CM-28900
Signed-off-by: Don Slice <dslice@cumulusnetworks.com>