soundwire: bus: add of_sdw_find_device_by_node helper

soundwire: bus: add of_sdw_find_device_by_node helper

There has been more than 3 instances of this helper in multiple codec
drivers, it does not make sense to keep duplicating this part of code.

Lets add a helper of_sdw_find_device_by_node for codec drivers to use it.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Link: https://patch.msgid.link/20250909121954.225833-4-srinivas.kandagatla@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>