d/ht_ctrl_emu: Stub set_output

src/xrt/drivers/ht_ctrl_emu/ht_ctrl_emu.cpp

@@ -356,6 +356,12 @@ cemu_device_get_tracked_pose(struct xrt_device *xdev,
 	}
 }
 
+static void
+cemu_device_set_output(struct xrt_device *xdev, enum xrt_output_name name, const union xrt_output_value *value)
+{
+	// No-op, needed to avoid crash.
+}
+
 //! @todo This is flickery; investigate once we get better hand tracking
 static void
 decide(xrt_vec3 one, xrt_vec3 two, bool *out)
@@ -435,6 +441,7 @@ cemu_devices_create(struct xrt_device *head, struct xrt_device *hands, struct xr
 
 		cemud[i]->base.update_inputs = cemu_device_update_inputs;
 		cemud[i]->base.get_tracked_pose = cemu_device_get_tracked_pose;
+		cemud[i]->base.set_output = cemu_device_set_output;
 		cemud[i]->base.get_hand_tracking = cemu_device_get_hand_tracking;
 		cemud[i]->base.destroy = cemu_device_destroy;