soc: samsung: exynos-pmu: fix device leak on regmap lookup

commit 990eb9a upstream.

Make sure to drop the reference taken when looking up the PMU device and
its regmap.

Note that holding a reference to a device does not prevent its regmap
from going away so there is no point in keeping the reference.

Fixes: 0b7c607 ("soc: samsung: exynos-pmu: Add regmap support for SoCs that protect PMU regs")
Cc: stable@vger.kernel.org	# 6.9
Cc: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251121121852.16825-1-johan@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: jhovold

drivers/soc/samsung/exynos-pmu.c

@@ -346,6 +346,8 @@ struct regmap *exynos_get_pmu_regmap_by_phandle(struct device_node *np,
 	if (!dev)
 		return ERR_PTR(-EPROBE_DEFER);
 
+	put_device(dev);
+
 	return syscon_node_to_regmap(pmu_np);
 }
 EXPORT_SYMBOL_GPL(exynos_get_pmu_regmap_by_phandle);