fixup: fix call to CJSModule

Author: MylesBorins

lib/internal/main/check_syntax.js

@@ -13,7 +13,7 @@ const {
 
 const { pathToFileURL } = require('url');
 
-const CJSModule = require('internal/modules/cjs/loader');
+let CJSModule;
 const vm = require('vm');
 const {
   stripShebang, stripBOM
@@ -27,6 +27,7 @@ if (process.argv[1] && process.argv[1] !== '-') {
 
   // TODO(joyeecheung): not every one of these are necessary
   prepareMainThreadExecution();
+  CJSModule = require('internal/modules/cjs/loader');
 
   // Read the source.
   const filename = CJSModule._resolveFilename(process.argv[1]);
@@ -40,6 +41,7 @@ if (process.argv[1] && process.argv[1] !== '-') {
 } else {
   // TODO(joyeecheung): not every one of these are necessary
   prepareMainThreadExecution();
+  CJSModule = require('internal/modules/cjs/loader');
   markBootstrapComplete();
 
   readStdin((code) => {