Fix recursion in filtered log call in validation used by log filter.
Fix recursion in filtered log call in validation used by log filter.

We can't log an IP address in a IP validation function which is used by
a log filter in `bridgedb.safelog`, because the log call made in the
validation function `bridgedb.parse.addr._isIPv()` will call the filter,
which will call the validation function, which will call the logger,
which will call the filter…

pagea/bridgedb,mmaker/bridgedb,mmaker/bridgedb,pagea/bridgedb