make floodnet bans use 'getmask' to not override blacklist/DNSBL/portscan bans

[empus]

Example:

--> | edge (~kim18fem@180.249.164.118) has joined #cservice
--> | Blownose (~bda@180.249.164.118) has joined #cservice
 -- | Mode #cservice [+b *!~*@180.249.164.118] by zen
<-- | zen has kicked Blownose (Armour: blacklisted (reason: (auto) join flood detected) [id: 215])
 -- | Mode #cservice [-b+b *!~*@180.249.164.118 *!*@180.249.164.118] by zen
<-- | zen has kicked edge (Armour: join flood detected)

Flodnet ban should have used !~@180.249.164.118