gnu: GStreamer plugins: Update MP3 features for GStreamer 1.14.

GStreamer moved all MPEG-1 audio (mp1, mp2, and mp3) decoders and encoders to
the group of "good" plugins in GStreamer 1.14.0. See the 'NEWS' file for more
information.

* gnu/packages/gstreamer.scm (gst-plugins-ugly)[inputs]: Remove lame, mpg123,
and twolame.
(gst-plugins-bad): Remove mpg123.
(gst-plugins-good): Add lame, mpg123, and twolame.

gnu/packages/gstreamer.scm

@@ -227,6 +227,7 @@ for the GStreamer multimedia library.")
        ("gdk-pixbuf" ,gdk-pixbuf)
        ("gst-plugins-base" ,gst-plugins-base)
        ("jack" ,jack-1)
+       ("lame" ,lame)
        ("libavc1394" ,libavc1394)
        ("libcaca" ,libcaca)
        ("libdv" ,libdv)
@@ -236,10 +237,12 @@ for the GStreamer multimedia library.")
        ("libshout" ,libshout)
        ("libsoup" ,libsoup)
        ("libvpx" ,libvpx)
+       ("mpg123" ,mpg123)
        ("orc" ,orc)
        ("pulseaudio" ,pulseaudio)
        ("speex" ,speex)
        ("taglib" ,taglib)
+       ("twolame" ,twolame)
        ("wavpack" ,wavpack)))
     (native-inputs
      `(("glib:bin" ,glib "bin")
@@ -320,7 +323,6 @@ developers consider to have good quality code and correct functionality.")
        ("libxml2" ,libxml2)
        ("lrdf" ,lrdf)
        ("mesa" ,mesa)
-       ("mpg123" ,mpg123)
        ("neon" ,neon)
        ("openal" ,openal)
        ("openexr" ,openexr)
@@ -357,13 +359,10 @@ par compared to the rest.")
     (inputs
      `(("gst-plugins-base" ,gst-plugins-base)
        ("liba52" ,liba52)
-       ("lame" ,lame)
        ("libcdio" ,libcdio)
-       ("twolame" ,twolame)
        ("libmpeg2" ,libmpeg2)
        ("libdvdread" ,libdvdread)
        ("libx264" ,libx264)
-       ("mpg123" ,mpg123)
        ;; TODO:
        ;; * opencore-amr (for the AMR-NB decoder and encoder and the
        ;;   AMR-WB decoder) <http://sourceforge.net/projects/opencore-amr/>