evdev: write EV_SYN input_event along with led events to device

Other clients of an evdev device need to have the events they receive
be separated, in moment in time, from other events by an EV_SYN/
SYN_REPORT. This is the responsibility of the client who writes events
into the stream.

src/evdev.c

@@ -45,7 +45,7 @@ evdev_led_update(struct evdev_device *device, enum weston_led leds)
 		{ LED_CAPS_LOCK, LED_CAPSL },
 		{ LED_SCROLL_LOCK, LED_SCROLLL },
 	};
-	struct input_event ev[ARRAY_LENGTH(map)];
+	struct input_event ev[ARRAY_LENGTH(map) + 1];
 	unsigned int i;
 
 	if (!device->caps & EVDEV_KEYBOARD)
@@ -57,6 +57,8 @@ evdev_led_update(struct evdev_device *device, enum weston_led leds)
 		ev[i].code = map[i].evdev;
 		ev[i].value = !!(leds & map[i].weston);
 	}
+	ev[i].type = EV_SYN;
+	ev[i].code = SYN_REPORT;
 
 	i = write(device->fd, ev, sizeof ev);
 	(void)i; /* no, we really don't care about the return value */