audiopolicy: fix crash in camcorder during voice call

- During an MO call when camcorder recording is done,
  a crash is observed for the first time.

- The crash is due to an assert that fails because an
  inappropriate value is returned.

- Fix the issue by returning NO_INIT to avoid the assert.

CRs-Fixed: 823350
Change-Id: Id83111957dab04a3db396401547989db8e8ed573