package/Config.in: fix make failure by removing gstreamer/Config.in

After commit:
https://git.buildroot.net/buildroot/commit/?id=fb49c7a26182f9d48f8283e7328fddc216962c94
gstreamer entry in package/Config.in was left behind resulting in every
make call to fail. So let's remove orphaned gstreamer entry from
package/Config.in

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/Config.in

@@ -26,7 +26,6 @@ menu "Audio and video applications"
 	source "package/fluid-soundfont/Config.in"
 	source "package/fluidsynth/Config.in"
 	source "package/gmrender-resurrect/Config.in"
-	source "package/gstreamer/Config.in"
 	source "package/gstreamer1/Config.in"
 	source "package/jack1/Config.in"
 	source "package/jack2/Config.in"