facedetector: Fix memory leak
facedetector: Fix memory leak

Change-Id: Ib9abe62a0962d883ea334e90705bcb4f3ac00b4b

Kurento/kms-filters,shelsonjava/kms-filters,shelsonjava/kms-filters,Kurento/kms-filters,shelsonjava/kms-filters,TribeMedia/kms-filters,Kurento/kms-filters,TribeMedia/kms-filters,TribeMedia/kms-filters