ASoC: qcom: q6apm-dai: fix race condition while updating the position pointer

It is noticed that the position pointer value seems to get a get corrupted
due to missing locking between updating and reading.

Fix this by adding a spinlock around the position pointer.

Fixes: 9b4fe0f1 ("ASoC: qdsp6: audioreach: add q6apm-dai support")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230209122806.18923-3-srinivas.kandagatla@linaro.org


Signed-off-by: Mark Brown <broonie@kernel.org>