tests: rtp-payloading avoid -Wmaybe-uninitialized
tests: rtp-payloading avoid -Wmaybe-uninitialized

More false positives as both of them are initialized in the line
before they are used, wrapped with fail_unless() check.

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