ASoC: SOF: Intel: hda: Fix NULL pointer dereference

ASoC: SOF: Intel: hda: Fix NULL pointer dereference

If there's a mismatch between the DAI links in the machine driver and
the topology, it is possible that the playback/capture widget is not
set, especially in the case of loopback capture for echo reference
where we use the dummy DAI link. Return the error when the widget is not
set to avoid a null pointer dereference like below when the topology is
broken.

RIP: 0010:hda_dai_get_ops.isra.0+0x14/0xa0 [snd_sof_intel_hda_common]

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: Mateusz Redzynia <mateuszx.redzynia@intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20260204081833.16630-10-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>