joystick: update scanner to match go-sdl 0.3 API changes

Signed-off-by: Ron Evans <ron@hybridgroup.com>

platforms/joystick/bin/scanner.go

@@ -44,18 +44,16 @@ func run() int {
 			case *sdl.JoyHatEvent:
 				fmt.Printf("[%d ms] Hat:%d\tvalue:%d\n",
 					t.Timestamp, t.Hat, t.Value)
-			case *sdl.JoyDeviceEvent:
-				if t.Type == sdl.JOYDEVICEADDED {
+			case *sdl.JoyDeviceAddedEvent:
 				joysticks[int(t.Which)] = sdl.JoystickOpen(int(t.Which))
 				if joysticks[int(t.Which)] != nil {
 					fmt.Printf("Joystick %d connected\n", t.Which)
 				}
-				} else if t.Type == sdl.JOYDEVICEREMOVED {
+			case *sdl.JoyDeviceRemovedEvent:
 				if joystick := joysticks[int(t.Which)]; joystick != nil {
 					joystick.Close()
 				}
 				fmt.Printf("Joystick %d disconnected\n", t.Which)
-				}
 			default:
 				fmt.Printf("Unknown event\n")
 			}