HyperV: wait on stop

When using podman machine with hyperv, stop was releasing the terminal
back top the user prematurely.  This resulted in users being able to run
subsequent commands while the vm was still stopped.  Commands like
machine stop were prone to failing.

[NO NEW TESTS NEEDED]

Signed-off-by: Brent Baude <bbaude@redhat.com>

vendor/github.com/containers/libhvee/pkg/hypervctl/vm.go

@@ -239,6 +239,17 @@ func (vm *VirtualMachine) Stop() error {
 		return translateShutdownError(int(res))
 	}
 
+	// Wait for vm to actually *be* down
+	for i := 0; i < 25; i++ {
+		refreshVM, err := vm.vmm.GetMachine(vm.ElementName)
+		if err != nil {
+			return err
+		}
+		if refreshVM.State() == Disabled {
+			break
+		}
+		time.Sleep(50 * time.Millisecond)
+	}
 	return nil
 }