mpeg2dec: initialize buffer
mpeg2dec: initialize buffer

Buffer needs to be null before passing it to gst_buffer_pool_acquire_buffer()

CID #1291634

GStreamer/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,shelsonjava/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,shelsonjava/gst-plugins-ugly,Kurento/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,Kurento/gst-plugins-ugly,freedesktop-unofficial-mirror/gstreamer__gst-plugins-ugly,GStreamer/gst-plugins-ugly,Kurento/gst-plugins-ugly,freedesktop-unofficial-mirror/gstreamer__gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,shelsonjava/gst-plugins-ugly,GStreamer/gst-plugins-ugly,freedesktop-unofficial-mirror/gstreamer__gst-plugins-ugly