util: named anonymous functions

PR-URL: #20408
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Weijia Wang <starkwang@126.com>
Reviewed-By: Matheus Marchini <matheus@sthima.com>

lib/util.js

@@ -277,12 +277,12 @@ function debuglog(set) {
   if (!debugs[set]) {
     if (debugEnvRegex.test(set)) {
       const pid = process.pid;
-      debugs[set] = function() {
+      debugs[set] = function debug() {
         const msg = exports.format.apply(exports, arguments);
         console.error('%s %d: %s', set, pid, msg);
       };
     } else {
-      debugs[set] = function() {};
+      debugs[set] = function debug() {};
     }
   }
   return debugs[set];