qtdemux: free seqh after calling qtdemux_parse_svq3_stsd_data()
qtdemux: free seqh after calling qtdemux_parse_svq3_stsd_data()

The seqh buffer allocated in qtdemux_parse_svq3_stsd_data() needs to
be freed by the caller after use.

https://bugzilla.gnome.org/show_bug.cgi?id=777157

Signed-off-by: Andre McCurdy <8f09cea6116be1c651ee99f9f5914cb35309ce01@gmail.com>

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