Most of these are not errors that are intended for the user, they are only
intended for developers so don't send them to PBD::error. The errors that may
be relevant to users should be handled in libardour or the GUI in response to
return values
I put these in libpbd as that is where the debug bits are for the Waves backend
but I think it makes more sense for them to be in libardour as that is where
the AudioBackend class is defined
I left the Waves debug bits in libpbd for now.
