Fix segmentation fault caused by NULL pointer access, REF 16142

Yalu Zhangrequested to merge
bug-16142 into asterisk_chan_voicemngr_rdkb

The chan_voicemngr_get_active_subchannel() can return NULL. But the returned value is not checked by all calling functions. This can cause a segmentation fault by NULL pointer access.

  • Check the returned value in all places calling chan_voicemngr_get_active_subchannel()
  • Pick some related changes from devel branch
Edited by Yalu Zhang

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