ASoC: pcm_dmaengine: Extract snd_dmaengine_pcm_refine_runtime_hwparams

When set the runtime hardware parameters, we may need to query
the capability of DMA to complete the parameters.

This patch is to Extract this operation from
dmaengine_pcm_set_runtime_hwparams function to a separate function
snd_dmaengine_pcm_refine_runtime_hwparams, that other components
which need this feature can call this function.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Link: https://lore.kernel.org/r/d728f65194e9978cbec4132b522d4fed420d704a.1569493933.git.shengjiu.wang@nxp.com


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