buffer: unconditionally use internalBinding

With the removal of test-buffer-bindingobj-no-zerofill.js,
internalBinding can be used unconditionally to assign
isAnyArrayBuffer().

PR-URL: #23234
Refs: #22160
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>

Author: cjihrig

lib/buffer.js

@@ -37,14 +37,7 @@ const {
   kMaxLength,
   kStringMaxLength
 } = process.binding('buffer');
-// We cannot use internalBinding unconditionally here because of the way
-// that test/parallel/test-buffer-bindingobj-no-zerofill.js is written.
-let isAnyArrayBuffer;
-try {
-  isAnyArrayBuffer = internalBinding('types').isAnyArrayBuffer;
-} catch (e) {
-  isAnyArrayBuffer = require('util').types.isAnyArrayBuffer;
-}
+const { isAnyArrayBuffer } = internalBinding('types');
 const {
   customInspectSymbol,
   isInsideNodeModules,