this patch added full context switch support for scheduling, it make sure
each VCPU has its own stack, and added host_sp field in struct sched_object
to record host stack pointer for each switch out object.
Arch related function arch_switch_to is added for context switch.
To benefit debugging, a name[] field is also added into struct sched_object.
Tracked-On: #2394
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Acked-by: Xu, Anthony <anthony.xu@intel.com>