ASoC: msm: qdsp6v2: Fix bugs in listen client and server

Correct LSM idx in APR sevices table. Free memory allocated for
snd_model when not needed. Unlock mutex before locking same mutex
again in the same thread.

CRs-Fixed: 487983
Change-Id: I392321cddfd53746f63955993801f523e17330f5
Signed-off-by: Kiran Kandi <kkandi@codeaurora.org>