LoongArch: Fix device node refcount leak in fdt_cpu_clk_init()

Add missing of_node_put() to properly handle the reference count of the
device node obtained from of_get_cpu_node().

Fixes: 44a01f1f726a ("LoongArch: Parsing CPU-related information from DTS")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>

arch/loongarch/kernel/env.c

@@ -68,6 +68,8 @@ static int __init fdt_cpu_clk_init(void)
 		return -ENODEV;
 
 	clk = of_clk_get(np, 0);
+	of_node_put(np);
+
 	if (IS_ERR(clk))
 		return -ENODEV;