amrnbdec: Don't use g_return_*_if_fail() on data parsing
amrnbdec: Don't use g_return_*_if_fail() on data parsing

Those functions can be disabled. Instead just use the (existing)
function.

CID #1427121

StreamUtils/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,GStreamer/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,GStreamer/gst-plugins-ugly,GStreamer/gst-plugins-ugly