sysmobts: Notify the BSC about all muted lchans
sysmobts: Notify the BSC about all muted lchans

Currently it takes some time (around 30s) until it is detected that
the radio link is down after mute. Not till then the BSC is informed
and the call terminated.

This patch modifies this behaviour by sending a RSL_MT_CONN_FAIL
message with cause RSL_ERR_RADIO_LINK_FAIL for each muted and active
lchan immediately after the corresponding Change Administrative State
Request has been acknowledged.

Ticket: OW#976
Sponsored-by: On-Waves ehf

telenoobie/osmo-bts,osmocom/osmo-bts,geosphere/osmo-bts,osmocom/osmo-bts,geosphere/osmo-bts,osmocom/osmo-bts,telenoobie/osmo-bts,geosphere/osmo-bts,geosphere/osmo-bts,telenoobie/osmo-bts,telenoobie/osmo-bts