Draft: onnx: adapt onnx object-detection to analytic meta
This MR modify Onnx object detection element and is build on top of MR 4962 to use analyticmeta to transport analytic metadata and their relations inside Gst pipeline. This MR is based on the current version of Onnx but will be adapted once MR 4916 as been merged. It allow to demonstrate the usage of analyticmeta.
To build it and obtain sample model refer to original Onnx MR: MR 1997
With only this MR nothing, is available to make use of analyticmeta but stay-tune others are one the way. One can use GST_DEBUG=anrelmeta:9 to monitor analytics metadata from logs.