compositemixer: Remove probe if it is necessary
compositemixer: Remove probe if it is necessary

Change-Id: I03f93922240d3d075c18f8241e9168fcf37d441a

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