Remove logger qlog

The root server tools had a separate logger in 'qlog.[ch]'. It was
merged with the client side logger 'log.[ch]' by commits: 4993e5517d,
06303f4f10 & 53e8c429f3. This was done to unify the sources and make
log format consistent across client & server tools. It simplifies
maintenance too.

Removed 'qlog' sources qlog.[ch], as they are no longer required.