regulator: of: Add a missing 'of_node_put()' in an error handling path of 'of_regulator_match()'

If an unlikely failure in 'of_get_regulator_init_data()' occurs, we must
release the reference on the current 'child' node before returning.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>