This allows specifying an alternate path for SOF firmware or
SOF topology.

This is particularly useful for i.MX when running Linux vs Android.
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20211005071949.1277613-1-daniel.baluta@oss.nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>