Move Conn::set_conn() from connection_state_remove to new_connection

c$conn is often needed for connection events, but it being established
in connection_state_removed can be a problem because event handlers have
to remember to call Con::set_conn().

This commit moves to call Conn::set_conn() in new_connection.

Addresses GH-4202

update logs

scripts/policy/protocols/conn/community-id-logging.zeek

@@ -17,10 +17,7 @@ export {
 	};
 }
 
-module Conn;
-
 event new_connection(c: connection) &priority=5
 	{
-	Conn::set_conn(c, F);  # likely first to access :-/
 	c$conn$community_id = community_id_v1(c$id, CommunityID::seed, CommunityID::do_base64);
 	}

scripts/policy/protocols/conn/failed-service-logging.zeek

@@ -30,8 +30,6 @@ event analyzer_failed(ts: time, atype: AllAnalyzers::Tag, info: AnalyzerViolatio
 	if ( analyzer_name !in c$service || analyzer_name in c$failed_analyzers )
 		return;
 
-	set_conn(c, F);
-
 	local aname = to_lower(Analyzer::name(atype));
 	# No duplicate logging
 	if ( c$conn?$failed_service && aname in c$conn$failed_service )

scripts/policy/protocols/conn/ip-proto-name-logging.zeek

@@ -12,8 +12,6 @@ redef record Info += {
 };
 
 event new_connection(c: connection) &priority=5 {
-	# In case we're the first access
-	Conn::set_conn(c, F);
 	if ( c$conn?$ip_proto && c$conn$ip_proto in IP::protocol_names )
 		c$conn$ip_proto_name = IP::protocol_names[c$conn$ip_proto];
 }

scripts/policy/protocols/conn/pppoe-session-id-logging.zeek

@@ -19,9 +19,6 @@ event new_connection(c: connection)
 	if ( session_id == 0xFFFFFFFF )
 		return;
 
-	# FIXME: remove when GH-4688 is merged
-	set_conn(c, F);
-
 	c$conn$pppoe_session_id = session_id;
 	}