Extend guest channel and sample apps to query CPU capabilities. Useful when a guest wants to see if there is a high frequency/priority core available for heavier workloads, i.e. Intel SST-BF.
The guest_cli implements an example of this via the query_cpu_caps cmd. Please note that these changes depend on (http://patches.dpdk.org/project/dpdk/list/?series=6568) and (http://patches.dpdk.org/project/dpdk/list/?series=6585) which should be applied first.
