ASoC: soc-acpi: remove sof_fw_filename

ASoC: soc-acpi: remove sof_fw_filename

We've been using a default firmware name for each PCI/ACPI/OF platform
for a while. The machine-specific sof_fw_filename is in practice not
different from the default, and newer devices don't set this field, so
let's remove the redundant definitions.

When OEMs modify the base firmware, they can keep the same firmware
name but store the file in a separate directory.

Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220301194903.60859-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>