ALSA: hda: intel-sdw-acpi: fix usage of device_get_named_child_node()

The documentation for device_get_named_child_node() mentions this
important point:

"
The caller is responsible for calling fwnode_handle_put() on the
returned fwnode pointer.
"

Add fwnode_handle_put() to avoid a leaked reference.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Fixes: 08c2a4bc ("ALSA: hda: move Intel SoundWire ACPI scan to dedicated module")
Message-ID: <20240426152731.38420-1-pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>