v4l2: Don't free props structure twice.
v4l2: Don't free props structure twice.

gst_v4l2_device_provider_probe_device() frees the passed props
structure, don't free it again in the caller.

pexip/gst-plugins-good,Kurento/gst-plugins-good,stfl/gst-plugins-good,hizukiayaka/gst-plugins-good,StreamUtils/gst-plugins-good,hizukiayaka/gst-plugins-good,hizukiayaka/gst-plugins-good,Kurento/gst-plugins-good,GrokImageCompression/gst-plugins-good,GStreamer/gst-plugins-good,stfl/gst-plugins-good,StreamUtils/gst-plugins-good,GStreamer/gst-plugins-good,pexip/gst-plugins-good,stfl/gst-plugins-good,stfl/gst-plugins-good,GrokImageCompression/gst-plugins-good,GStreamer/gst-plugins-good,GrokImageCompression/gst-plugins-good,hizukiayaka/gst-plugins-good,Kurento/gst-plugins-good,pexip/gst-plugins-good,GrokImageCompression/gst-plugins-good,StreamUtils/gst-plugins-good,pexip/gst-plugins-good,Kurento/gst-plugins-good,Kurento/gst-plugins-good,StreamUtils/gst-plugins-good,pexip/gst-plugins-good,GStreamer/gst-plugins-good