style: satisfy golangci-lint on the round-6 changes

nolintlint: gosec was not firing on the deferred Close.
nonamedreturns + varnamelen in collapseUserModeOps.

internal/ircserver/conn.go

@@ -161,7 +161,7 @@ func (c *Conn) Disconnect(reason string) {
 func (c *Conn) notifyKilledAndClose(
 	nick, host, reason string,
 ) {
-	defer c.conn.Close() //nolint:errcheck,gosec
+	defer c.conn.Close() //nolint:errcheck
 
 	c.sendWithin(
 		killWriteWindow,

internal/service/service.go

@@ -1070,20 +1070,22 @@ func isKnownUserModeChar(modeChar rune) bool {
 // defence-in-depth only.
 func collapseUserModeOps(
 	ops []userModeOp,
-) (wallops, oper *bool, err error) {
+) (*bool, *bool, error) {
 	unknownFlag := &IRCError{
 		Code:    irc.ErrUmodeUnknownFlag,
 		Params:  nil,
 		Message: "Unknown MODE flag",
 	}
 
-	for _, op := range ops {
+	var wallops, oper *bool
-		switch op.char {
+
+	for _, modeOp := range ops {
+		switch modeOp.char {
 		case 'w':
-			val := op.adding
+			val := modeOp.adding
 			wallops = &val
 		case 'o':
-			if op.adding {
+			if modeOp.adding {
 				return nil, nil, unknownFlag
 			}