New API: set_pstate_speed
Create CPU resource in Hosts (physical and VM)
While we don't decide to expose the Cpu to users, move the CPU creation to the s4u::Host.
Remove another indirection of CPU class setting the pimpl_cpu of Host class. A small step towards encapsulation..
Propose new API to set pstate for a host:
- Host* Host::set_pstate_speed(const std::vector& speed_per_state)
- Host* Host::set_pstate_speed(const std::vectorstd::string& speed_per_state)