cronyx: trivial cleanups

Signed-off-by: Volokh Konstantin <volokh84@gmail.com>
cronyx: tau32 supports for dahdi
  get_device returns handle on device for registrations in dahdi

Signed-off-by: Volokh Konstantin <volokh84@gmail.com>
cronyx: tauisa isa driver prototype

Signed-off-by: Volokh Konstantin <volokh84@gmail.com>