KVM: Portability: Add two hooks to handle kvm_create and destroy vm

Add two arch hooks to handle kvm_create_vm and kvm destroy_vm. Now, just
put io_bus init and destory in common.

Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index c4ad66b..59e001c 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -674,6 +674,10 @@
 void kvm_arch_hardware_unsetup(void);
 void kvm_arch_check_processor_compat(void *rtn);
 
+void kvm_free_physmem(struct kvm *kvm);
+
+struct  kvm *kvm_arch_create_vm(void);
+void kvm_arch_destroy_vm(struct kvm *kvm);
 
 static inline void kvm_guest_enter(void)
 {