Input: sparcspkr - use cleanup facility for device_node

Use the 'free(device_node)' macro to simplify the code by automatically
freeing the device node, which removes the need for explicit calls to
'of_node_put()'.

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20241021-input_automate_of_node_put-v3-2-cc73f636e1bc@gmail.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>