fix freshclam startup

- create pid file in existing folder /run
- let freshclam log to stdout
- remove deprecated SafeBrowsing

optional/clamav/conf/freshclam.conf

@@ -3,9 +3,9 @@
 ###############
 
 DatabaseDirectory /data
-LogSyslog yes
+UpdateLogFile /dev/stdout
 LogTime yes
-PidFile /run/clamav/freshclam.pid
+PidFile /run/freshclam.pid
 DatabaseOwner root
 
 ###############
@@ -15,5 +15,4 @@ DatabaseOwner root
 DatabaseMirror database.clamav.net
 ScriptedUpdates yes
 NotifyClamd /etc/clamav/clamd.conf
-SafeBrowsing yes
 Bytecode yes