soundwire: intel: remove PDM support

soundwire: intel: remove PDM support

While the hardware supports PDM streams, this capability has never
been tested or enabled on any product, so this is dead-code. Let's
remove all this.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20211224021034.26635-8-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>