net: stmmac: dwmac-sun8i: add missing of_node_put() in sun8i_dwmac_register_mdio_mux()

stable inclusion
from stable-v5.10.115
commit 4eee9809505cc444ab32b71f55c65f81d5f23716
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5IZ9C

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4eee9809505cc444ab32b71f55c65f81d5f23716



--------------------------------

commit 1a15267b upstream.

The node pointer returned by of_get_child_by_name() with refcount incremented,
so add of_node_put() after using it.

Fixes: 634db83b ("net: stmmac: dwmac-sun8i: Handle integrated/external MDIOs")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220428095716.540452-1-yangyingliang@huawei.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>