util: simplify code

Simplify code by using return value of Object.defineProperty directly.

PR-URL: #25162
Reviewed-By: Vladimir de Turckheim <vlad2t@hotmail.com>
Reviewed-By: Masashi Hirano <shisama07@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/internal/util.js

@@ -260,10 +260,9 @@ function promisify(original) {
  if (typeof fn !== 'function') {
  throw new ERR_INVALID_ARG_TYPE('util.promisify.custom', 'Function', fn);
  }
- Object.defineProperty(fn, kCustomPromisifiedSymbol, {
+ return Object.defineProperty(fn, kCustomPromisifiedSymbol, {
  value: fn, enumerable: false, writable: false, configurable: true
  });
- return fn;
  }
 
  // Names to create an object from in case the callback receives multiple