tools: L2 CAT: support set cbm for L2 CAT.

tools: L2 CAT: support set cbm for L2 CAT.

This patch implements the xl/xc changes to support set CBM
for L2 CAT.

The new level option is introduced to original CAT setting
command in order to set CBM for specified level CAT.
- 'xl psr-cat-set' is updated to set cache capacity bitmasks(CBM)
  for a domain according to input cache level.

root@:~$ xl psr-cat-set -l2 1 0x7f

root@:~$ xl psr-cat-show -l2 1
Socket ID       : 0
Default CBM     : 0xff
   ID                     NAME             CBM
    1                 ubuntu14            0x7f

Signed-off-by: He Chen <he.chen@linux.intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>