filterelement: Remove input and output adapters
filterelement: Remove input and output adapters

They are negotiated by the agnosticbin if it is needed

Change-Id: I7d081c488a9e43175c7b89cf2d79273e91122268

shelsonjava/kms-core,KurentoLegacy/gst-kurento-plugins,KurentoLegacy/gst-kurento-plugins,TribeMedia/kms-core,ESTOS/kms-core,ESTOS/kms-core,Kurento/kms-core,Kurento/kms-core,shelsonjava/kms-core,TribeMedia/kms-core,shelsonjava/kms-core,Kurento/kms-core,ESTOS/kms-core,Kurento/kms-core,KurentoLegacy/gst-kurento-plugins,KurentoLegacy/gst-kurento-plugins,shelsonjava/kms-core,TribeMedia/kms-core,TribeMedia/kms-core,ESTOS/kms-core