cmetrics: remove dead code in mpam_ctrlmon.c and resctrlfs.c

hulk inclusion
category: feature
feature: ARM MPAM support
bugzilla: 48265
CVE: NA

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Cmetrics scanned out these dead code. Let's remove them.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>