BUG/MAJOR: backend: only update server's counters when the server exists

PiBa-NL reported that since this commit f157384 ("MINOR: backend: count
the number of connect and reuse per server and per backend"), reg-test
connection/h00001 fails. Indeed it does, the server is not checked for
existing prior to updating its counter. It should also fail with
transparent mode.
1 file changed