IrcBufferModel: don't create "*" buffers
IrcBufferModel: don't create "*" buffers

Take a step back. b53775b changed things so that no buffers would be
created when the name contained an asterisk. This does not play nice
with the default ZNC prefix.

jpnurmi/libcommuni,jpnurmi/libcommuni,communi/libcommuni,communi/libcommuni