pathd: rework debugs

pathd: rework debugs

Pathd uses a single debug struct with additional option flags to
configure different types of debug messages. This is not how debug
library is supposed to be used. The idea of option flags is to allow
more granular control of a single type, not to represent multiple types.

This commit adds a separate debug struct for each type which greatly
simplifies the code.

Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>