arm64/mpam: Simplify mpamid cdp mapping process

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

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MPAM includes partid, pmg, monitor, all of these we collectively call
mpam id, if cdp on, we would allocate a new mpamid_new which equals to
mpamid + 1, and at some places mpamid may not need to be encapsulated
into struct { u16 val; } for simplicity, So we use a simpler macro
resctrl_cdp_mpamid_map_val() to complete this cdp mapping process.

Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>