Add length to write command packet token so that we can track exactly how many bytes are consumed by DSP in the command reply. This is useful in some use-cases where the end of the file/stream is not aligned with period size. Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Tested-by: Vinod Koul <vkoul@kernel.org> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by: Vinod Koul <vkoul@kernel.org> Link: https://lore.kernel.org/r/20200727093806.17089-5-srinivas.kandagatla@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>