In the case where you're echoing back a tx-abort, just let it through.
Not doing this causes problems in the case where your node has forgotten
about an in-progress open.
This fixes the following problem:
- you send a tx-abort (even tho you have marked tx-sigs as received)
- peer echos it back (we echo back tx-aborts always)
- you throw an error because you're already in a tx-abort unallowed
state
In this commit, we allow for echos to come thru no matter our current state and
this fixes things/makes them work as expected.
b2d2796aad