repl: remove unused function

replStart() was defined but never used. The function has been removed.
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Chris Dickinson <christopher.s.dickinson@gmail.com>

lib/internal/repl.js

@@ -14,12 +14,6 @@ module.exports.createInternalRepl = createRepl;
 // The debounce is to guard against code pasted into the REPL.
 const kDebounceHistoryMS = 15;
 
-// XXX(chrisdickinson): hack to make sure that the internal debugger
-// uses the original repl.
-function replStart() {
-  return REPL.start.apply(REPL, arguments);
-}
-
 function createRepl(env, opts, cb) {
   if (typeof opts === 'function') {
     cb = opts;