ARM: exynos: Fix refcount leak in exynos_map_pmu

stable inclusion
from stable-v5.10.127
commit 68f28d52e6cbab8dcfa249cac4356d1d0573e868
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5XDDK

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=68f28d52e6cbab8dcfa249cac4356d1d0573e868

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

commit c4c79525 upstream.

of_find_matching_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.
of_node_put() checks null pointer.

Fixes: fce9e5bb ("ARM: EXYNOS: Add support for mapping PMU base address via DT")
Signed-off-by: NMiaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220523145513.12341-1-linmq006@gmail.comSigned-off-by: NKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>

arch/arm/mach-exynos/exynos.c

@@ -149,6 +149,7 @@ static void exynos_map_pmu(void)
 	np = of_find_matching_node(NULL, exynos_dt_pmu_match);
 	if (np)
 		pmu_base_addr = of_iomap(np, 0);
+	of_node_put(np);
 }
 
 static void __init exynos_init_irq(void)