ASoC: msm-lsm-client: Fix null pointer dereference

There is possible null pointer dereference in the lsm driver. Fix this
to avoid null pointer dereference which results in device crash.

Change-Id: I6b24c3798417c9d15e3770728558b25d86f0101d
Signed-off-by: Bhalchandra Gajare <gajare@codeaurora.org>
Signed-off-by: Vidyakumar Athota <vathota@codeaurora.org>