Release v2.3.4

Lino Sanfilippo (7):
      Use lock to check pibridge state
      Remove unused counter for open instances
      Make function waitRunning() static
      In piControlOpen() do not reset piControl
      Return correct error code if memory allocation failed in piControlOpen
      Retry if flash erase during firmware update failed
      compact: in cycle timer use completion instead of work queue

Ramiro Gsponer (1):
      Release v2.3.4