avpops: create a local pv structure when parameter is only flags

- flags details are stored inside it
- fixes crash at startup reported by Kevin Scott Adams, FS#381

(cherry picked from commit 3c88f1de9d647db8a14bae45af1fa3b34f74d4e6)
tm: reset temporary linking of reply to transaction after branch failure route execution

- reported by Robert Boisvert, FS#379

(cherry picked from commit 0ebc983a422cd5ee4baa39bb3ef3bdbeeefd4571)