powerpc/xive: Fix refcount leak in xive_get_max_prio

stable inclusion
from stable-v5.10.137
commit 6d1e53f7f181a11a8a343def1e0d0209905b7c64
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6d1e53f7f181a11a8a343def1e0d0209905b7c64



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[ Upstream commit 255b650c ]

of_find_node_by_path() returns a node pointer with
refcount incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.

Fixes: eac1e731 ("powerpc/xive: guest exploitation of the XIVE interrupt controller")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220605053225.56125-1-linmq006@gmail.com


Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>