kmsbitratefilter: update src caps with bitrate
kmsbitratefilter: update src caps with bitrate

Change-Id: Ic3b3900688f9b0a2ecd98c1ea3113816a1a6690b

TribeMedia/kms-core,Kurento/kms-core,shelsonjava/kms-core,TribeMedia/kms-core,Kurento/kms-core,shelsonjava/kms-core,ESTOS/kms-core,ESTOS/kms-core,shelsonjava/kms-core,TribeMedia/kms-core,ESTOS/kms-core,Kurento/kms-core,TribeMedia/kms-core,ESTOS/kms-core,Kurento/kms-core,shelsonjava/kms-core