sctpassociation: remove redundant number_of_associations.
sctpassociation: remove redundant number_of_associations.

We can adequately use the size of the associations
hash table instead of this variable.

sancane/openwebrtc-gst-plugins,EricssonResearch/openwebrtc-gst-plugins,sancane/openwebrtc-gst-plugins,sancane/openwebrtc-gst-plugins,EricssonResearch/openwebrtc-gst-plugins,EricssonResearch/openwebrtc-gst-plugins