platedetector: Remove unneeded field in private structure
platedetector: Remove unneeded field in private structure

Change-Id: Ic04b271bd9ccc50d5ef0c0af26176f26fef75682

Kurento/kms-platedetector,Kurento/kms-platedetector,dfernandezlop/kms-platedetector,Kurento/kms-platedetector,dfernandezlop/kms-platedetector,shelsonjava/kms-platedetector,shelsonjava/kms-platedetector,dfernandezlop/kms-platedetector,shelsonjava/kms-platedetector