scaletempo: Advertise interleaved layout in caps templates
scaletempo: Advertise interleaved layout in caps templates

Scaletempo doesn't support non-interleaved layout. Not explicitely stating this
would trigger critical warnings and a caps negotiation failure when scaletempo
is used as playbin audio-filter.

Patch suggested by George Kiagiadakis <george.kiagiadakis@collabora.com>.

Fixes #591

GStreamer/gst-plugins-good,GStreamer/gst-plugins-good,pexip/gst-plugins-good,GStreamer/gst-plugins-good,GStreamer/gst-plugins-good,pexip/gst-plugins-good,pexip/gst-plugins-good,pexip/gst-plugins-good,pexip/gst-plugins-good