regulator: s5m8767: Fix reference count leak

Call of_node_put() to drop references of regulators_np and reg_np before
returning error code.

Fixes: 9ae5cc75 ("regulator: s5m8767: Pass descriptor instead of GPIO number")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20210121032756.49501-1-bianpan2016@163.com


Signed-off-by: Mark Brown <broonie@kernel.org>