device-monitor: Stop createing duplicated CameraDevices
Devices detected in cheese_camera_device_monitor_coldplug()
may get
duplicated, as Gstreamer will emit GST_MESSAGE_DEVICE_ADDED
for them.
While this issue could be fixed by reorganizing the initialization code,
let's go with a simple and robust solution and check if a
CheeseCameraDevice
using the GstDevice
is already present.
Closes #130 (closed)