ChanServ, OpServ and main.c bug fixes

* Read new-style channel flags from the correct field, and do not make
ChanServ rejoin channels that are still suspended

* Allow service nicknames to be omitted from srvx.conf (again)

* Construct "opserv" bot earlier so that database read works correctly
git-archimport-id: srvx@srvx.net--2004-srvx/srvx--devo--1.3--patch-6