soc: qcom: ocmem: use scoped device node handling to simplify error paths

Obtain the device node reference with scoped/cleanup.h to reduce error
handling and make the code a bit simpler.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240813-b4-cleanup-h-of-node-put-other-v1-4-cfb67323a95c@linaro.orgSigned-off-by: Bjorn Andersson <andersson@kernel.org>

drivers/soc/qcom/ocmem.c

@@ -186,23 +186,20 @@ static void update_range(struct ocmem *ocmem, struct ocmem_buf *buf,
 struct ocmem *of_get_ocmem(struct device *dev)
 {
 	struct platform_device *pdev;
-	struct device_node *devnode;
 	struct ocmem *ocmem;
 
-	devnode = of_parse_phandle(dev->of_node, "sram", 0);
+	struct device_node *devnode __free(device_node) = of_parse_phandle(dev->of_node,
+									   "sram", 0);
 	if (!devnode || !devnode->parent) {
 		dev_err(dev, "Cannot look up sram phandle\n");
-		of_node_put(devnode);
 		return ERR_PTR(-ENODEV);
 	}
 
 	pdev = of_find_device_by_node(devnode->parent);
 	if (!pdev) {
 		dev_err(dev, "Cannot find device node %s\n", devnode->name);
-		of_node_put(devnode);
 		return ERR_PTR(-EPROBE_DEFER);
 	}
-	of_node_put(devnode);
 
 	ocmem = platform_get_drvdata(pdev);
 	if (!ocmem) {