wasapi: Speed up enumerate_devices by caching default device IDs for each flow/role instead of requerying for every wasapi_create_device.
wasapi: Speed up enumerate_devices by caching default device IDs for each flow/role instead of requerying for every wasapi_create_device.

Locally (on a machine with ~120 devices), this reduces a single
enumerate_devices call from ~1100ms to ~250ms.

kinetiknz/cubeb,kinetiknz/cubeb,kinetiknz/cubeb