Revert to default 6 ssh/ddos login attempts

No legitimate admin will require 20 login attempts. The default 6 is a sane middle ground especially since in 10 minutes they can try again  or immediately from another IP anyway.

conf/fail2ban/jail.local

@@ -8,12 +8,8 @@ maxretry = 20
 
 # JAILS
 
-[ssh]
-maxretry = 20
-
 [ssh-ddos]
 enabled  = true
-maxretry = 20
 
 [sasl]
 enabled  = true