ASoC: msm: Clear calibration data if there are no clients

Destroy all calibration data active if all references
to the calibration driver are closed. This ensures that
there are no memory leaks when userspace clients are
destroyed.

Change-Id: I31b45ceb126b5d19208c30230b9f4ac6d19a5570
Signed-off-by: Ben Romberger <bromberg@codeaurora.org>