arm64/mpam: resctrl: add tips when rmid modification failed

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4LMMF


CVE: NA

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This adds tips when rmid modification failed.

Fixes: a85aba6a ("mpam: Add support for group rmid modify")
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>