arm64/mpam: fix the problem that the ret variable is not initialized

kylin inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4AHUL?from=project-issue
CVE: NA

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initialize the value "ret" in "schemata_list_init()"
Signed-off-by: N温志伟 <wenzhiwei@kylinos.cn>
Reviewed-by: Jian Cheng <cj.chengjian(a)huawei.com>
Signed-off-by: NWang ShaoBo <bobo.shaobowang@huawei.com>

arch/arm64/kernel/mpam/mpam_ctrlmon.c

@@ -127,7 +127,7 @@ static int add_schema(enum resctrl_conf_type t, struct resctrl_resource *r)
 
 int schemata_list_init(void)
 {
-	int ret;
+	int ret = 0;
 	struct mpam_resctrl_res *res;
 	struct resctrl_resource *r;