lchan: Release the lchan more quickly, align with GSM 04.08

* Release all channels with SAPI > 0 with the "local end release"
  (as of NOTE 1 of GSM 04.08).
* No need to wait for all SAPIs to be torn down and the normal
  REL_IND/REL_CONF will call rsl_handle_release and the channel
  should be released.
* Update the documentation
5 files changed
tree: f4b9cf4116e054bb8cc03d72efda40328c0b17e3
  1. debian/
  2. hlrsync/
  3. linux-kernel/
  4. openbsc/
  5. wireshark/
  6. README