ARM: hisi: Add missing of_node_put after of_find_compatible_node

of_find_compatible_node  will increment the refcount of the returned
device_node. Calling of_node_put() to avoid the refcount leak

Signed-off-by: Peng Wu <wupeng58@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>