Current codec API for choosing remote endpoint was not suitable for
implementing fallback to another endpoint when first chosen one was not
possible to establish.

To overcome this problem change codec API to rather provide generic method
for comparing two endpoints by their capabilities. Return value is standard
value what comparator function returns (-1, 0, 1). It can be used e.g. for
searching the best remote endpoint (like did previous API method) or
creating a full list of all endpoints in preferred order (e.g. by sorting
function).

Currently this method is not used (neither old choose remote endpoint).
It is used by code for switching A2DP codec which is in next patches.