This property indicates whether the filter can be directly linked with clients
that have a defined target (Eg: pw-play --target <filter-name>) or not. This can
be useful when a client wants to be linked with a filter that is in the middle
of the chain in order to bypass the filters that are placed before the selected
one. If the property is not set, wireplumber will consider the filter not
targetable by default, meaning filters will never by bypassed by clients, and
clients will always be linked with the first filter in the chain.
Fixes#554
598b3c83ce