ASoC: SOF: Implement snd_sof_bytes_ext_volatile_get kcontrol IO

This patch implements the snd_sof_bytes_ext_volatile_get() to read the
actual parameters from DSP by sending the SOF_IPC_COMP_GET_DATA IPC
for the kcontrol of type SOF_TPLG_KCTL_BYTES_VOLATILE_RO.

Signed-off-by: Dharageswari R <dharageswari.r@intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200908092825.1813847-2-kai.vehmanen@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>