tools: CMDs and APIs for Cache Monitoring Technology

tools: CMDs and APIs for Cache Monitoring Technology

Introduced some new xl commands to enable/disable Cache Monitoring
Technology(CMT) feature.

The following two commands is to attach/detach the CMT feature
to/from a certain domain.

$ xl psr-cmt-attach domid
$ xl psr-cmt-detach domid

This command is to display the CMT information, such as L3 cache
occupancy.

$ xl psr-cmt-show cache_occupancy <domid>

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>