There seems to be issues with the write handling of the osmo-stp
and so far we did not enable vty tests here. Make it possible to
enable the tests, fix the VTY strings, change string to OsmoSTP.
Change-Id: I547fd4840d86ce16e8589fb63802dd7099781194
It appears that it is possible to have a stale SCTP connection
and this added LOGL_NOTICE and the VTY interface might help to
identify this situation in the future (the mean time of failure
is about five month).
This new interface allows to have multiple linksets, msc
connections and ways to connect those in one instance of
the osmo-stp. Forbid to reset linksets without an app.