Include the write lock since we're changing the tech_pvt
Seems having a read lock still prevents a write lock to be taken, even if the thread that is trying to get the write lock currently has the read lock.
Seems the session wasn't coming to the hangup in a locked state.
Since there isn't neutral ground, on the rtmp state callback we actually have to force the write lock of the session, but we only need a try lock on removing the session from the rsession->session_hash. This removes a deadlock caused when we had to enforce with locks that the rsession couldn't be destroyed if the FS session was in the middle of a hangup.
how...?