ASoC: qcom: pass direction to dma allocation

This patch updates the internal dma allocation callbacks to take the
stream direction so that it can allocate channels suitable for that
stream direction. Before the capture support this was not necessary.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Kenneth Westfield <kwestfie@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>