The s390 CPU state can be retrieved without interrupting the
VM execution. Extendend the CpuInfoFast union with architecture
specific data and an implementation for s390.

Return data looks like this:
 [
   {"thread-id":64301,"props":{"core-id":0},
    "arch":"s390","cpu-state":"operating",
    "qom-path":"/machine/unattached/device[0]","cpu-index":0},
   {"thread-id":64302,"props":{"core-id":1},
    "arch":"s390","cpu-state":"operating",
    "qom-path":"/machine/unattached/device[1]","cpu-index":1}
]
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1518797321-28356-4-git-send-email-mihajlov@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>