memory: atmel-ebi: add missing of_node_put for loop iteration

Early exits from for_each_available_child_of_node() should decrement the
node reference counter.  Reported by Coccinelle:

  drivers/memory/atmel-ebi.c:593:1-33: WARNING:
    Function "for_each_available_child_of_node" should have of_node_put() before return around line 604.

Fixes: 6a4ec4cd ("memory: add Atmel EBI (External Bus Interface) driver")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210423101815.119341-2-krzysztof.kozlowski@canonical.com

drivers/memory/atmel-ebi.c

@@ -600,10 +600,12 @@ static int atmel_ebi_probe(struct platform_device *pdev)
 				child);
 
 			ret = atmel_ebi_dev_disable(ebi, child);
-			if (ret)
+			if (ret) {
+				of_node_put(child);
 				return ret;
 			}
 		}
+	}
 
 	return of_platform_populate(np, NULL, NULL, dev);
 }