HV: validate target vm in hypercall

- The target vm in most of hypercalls should be a NORMAL_VM, in some
exceptions it might be a SOS_VM, we should validate them.

- Please be aware that some hypercall might have limitation on specific
target vm like RT or SAFETY VMs, this leaves "TODO" in future;

- Unify the coding style:

	int32_t hcall_foo(vm, target_vm_id, ...)
	{
		int32_t ret = -1;
		...

		if ((is_valid_vm(target_vm) && is_normal_vm(target_vm)) {
			ret = ....
		}

		return ret;
	}

Tracked-On: #2978

Signed-off-by: Victor Sun <victor.sun@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/arch/x86/guest/vm.c

@@ -57,6 +57,15 @@ bool is_sos_vm(const struct acrn_vm *vm)
 	return (vm != NULL)  && (get_vm_config(vm->vm_id)->type == SOS_VM);
 }
 
+/**
+ * @pre vm != NULL
+ * @pre vm->vmid < CONFIG_MAX_VM_NUM
+ */
+bool is_normal_vm(const struct acrn_vm *vm)
+{
+	return (get_vm_config(vm->vm_id)->type == NORMAL_VM);
+}
+
 /**
  * @pre vm != NULL
  * @pre vm->vmid < CONFIG_MAX_VM_NUM