module: exclude node:ffi from builtinModules when flag is disabled

Module.builtinModules is supposed to only list modules that are accessible to user code.
node:ffi requires --experimental-ffi to be required,
so filter it out when the flag is not set,
mirroring the existing handling for --experimental-quic.

Refs: #63137 (comment)

Author: ljharb

lib/internal/modules/cjs/loader.js

@@ -490,6 +490,9 @@ function initializeCJS() {
   if (!getOptionValue('--experimental-quic')) {
     modules = modules.filter((i) => i !== 'node:quic');
   }
+  if (!getOptionValue('--experimental-ffi')) {
+    modules = modules.filter((i) => i !== 'node:ffi');
+  }
   Module.builtinModules = ObjectFreeze(modules);
 
   initializeCjsConditions();