configure: Use -Bsymbolic-functions if available
configure: Use -Bsymbolic-functions if available

While this is more useful for libraries, some of our plugins with multiple
files and some internal API can also benefit from this.

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