ASoC: SOF: mediatek: Add mediatek common debug dump

1.Add mtk-adsp-common.c file for mediatek platforms common usage.
2.Add mtk_adsp_dump implementation in mtk-adsp-common.c for general
debug dump.

Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: YC Hung <yc.hung@mediatek.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220517173109.468568-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>