PM / devfreq: exynos-ppmu: Fix refcount leak in of_get_devfreq_events

stable inclusion
from stable-v5.10.129
commit e65027fdebbacd40595e96ef7b5d2418f71bddf2
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5YNDQ

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e65027fdebbacd40595e96ef7b5d2418f71bddf2



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commit f44b7996 upstream.

of_get_child_by_name() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
This function only calls of_node_put() in normal path,
missing it in error paths.
Add missing of_node_put() to avoid refcount leak.

Fixes: f262f28c ("PM / devfreq: event: Add devfreq_event class")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>