Add a new PortConfig parameter to configure ports of elements that
are marked with the SPA_NODE_FLAG_*_PORT_CONFIG. This is used to
configure the operation of the audioconver/audioadapter nodes and
how it should convert the internal format. We want to use the
Profile parameter only for cases where there is an enumeration of
values, like with device configuration.
Add unit tests for audioconvert and adapter to check if they handle
PortConfig correctly.
Make the media session use the PortConfig to dynamically configure
the device nodes.
Remove audio-dsp, it is not used anymore and can/should be implemented
with a simple audioconvert spa node now and some PortConfig.
Remove the spa_pod_iter helpers
Remove builder/parser vararg recurse option, you have to
manually recurse into structures when needed. This simplifies
things a lot.
Pass spa_pod_frames to builder and parser explicitly, we don't
have to keep an internal stack anymore.
The parser is now almost a mirror image of the builder.
Make the parser safer when iterating over objects, add functions
to check and get pod contents in a safe way.
Make the builder return errno style results on errors
Improve performance of object properties when they are stored and
retrieved in the same order.
Add many more tests for the builder and parser
Add some benchmarks
