[CORE] Add vmm_manager_vcpu_hcpu_resched() & vmm_manager_vcpu_hcpu_func() APIs

This patch adds two new useful APIs to vmm_manager for SMP host:
1. vmm_manager_vcpu_hcpu_resched() - This API forces rescheduling on the
host CPU assigned to given VCPU.
2. vmm_manager_vcpu_hcpu_func() - This API helps us call a function on
the host CPU assigned to given VCPU.

Signed-off-by: Anup Patel <anup@brainfault.org>