touchpad: explicitly start with detect_thumbs as false

Not needed because we zalloc() anyway, but this makes it grep-able.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

src/evdev-mt-touchpad-thumb.c

@@ -158,6 +158,8 @@ tp_init_thumb(struct tp_dispatch *tp)
 	struct quirks_context *quirks;
 	struct quirks *q;
 
+	tp->thumb.detect_thumbs = false;
+
 	if (!tp->buttons.is_clickpad)
 		return;