For Pro Audio devices, the description is the card name with "Pro" or
Pro 1", "Pro 2", etc. appended. The result is user interfaces showing
around half a dozen devices with descriptions that don't help
disambiguate devices in the slightest.
Append the underlying PCM names instead of the "Pro N" string, so that
devices can be recognised at a glance.
Fixes: https://gitlab.freedesktop.org/pipewire/pipewire/-/work_items/3982