buffer: use v8::TypedArray::kMaxLength as buffer::kMaxLength

This was added in v8 6.2, looks like a safe replacement for
our own buffer::kMaxLength.

PR-URL: https://github.com/nodejs/node/pull/19738


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>