pmdomain: imx: gpcv2: fix an OF node reference leak in imx_gpcv2_probe()

imx_gpcv2_probe() leaks an OF node reference obtained by
of_get_child_by_name(). Fix it by declaring the device node with the
__free(device_node) cleanup construct.

This bug was found by an experimental static analysis tool that I am
developing.

Fixes: 03aa126 ("soc: imx: Add GPCv2 power gating driver")
Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
Cc: stable@vger.kernel.org
Message-ID: <20241215030159.1526624-1-joe@pf.is.s.u-tokyo.ac.jp>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: joehattori

drivers/pmdomain/imx/gpcv2.c

@@ -1458,12 +1458,12 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
 		.max_register   = SZ_4K,
 	};
 	struct device *dev = &pdev->dev;
-	struct device_node *pgc_np;
+	struct device_node *pgc_np __free(device_node) =
+		of_get_child_by_name(dev->of_node, "pgc");
 	struct regmap *regmap;
 	void __iomem *base;
 	int ret;
 
-	pgc_np = of_get_child_by_name(dev->of_node, "pgc");
 	if (!pgc_np) {
 		dev_err(dev, "No power domains specified in DT\n");
 		return -EINVAL;