ASoC: sdca: test adev before calling acpi_dev_for_each_child

ASoC: sdca: test adev before calling acpi_dev_for_each_child

sdca_lookup_functions may be called by a Peripheral that is not listed
in the ACPI table. Testing adev is required to avoid kernel NULL pointer
dereference.

Fixes: 3a513da1ae33 ("ASoC: SDCA: add initial module")
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://patch.msgid.link/20241113064133.162501-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>