bridge: Resend status changes to database if previous transaction
was not successful.

Bridge, port and interface status changes are not sent to the
database if the connectivity and netdev sequence numbers have not
changed. However, if the previous database transaction fails, then
status changes will not be updated in the database until the
connectivity and netdev sequence numbers change again. This could
leave the database in an incorrect state for a long period of time.

This patch always sends status changes to the database if the last
transaction was not successful.

Bug #1256577
Signed-off-by: Ryan Wilson <wryan@nicira.com>
Acked-by: Alex Wang <alexw@nicira.com>
Signed-off-by: Alex Wang <alexw@nicira.com>