Create a file to centralize argument validators that are used in
multiple internal modules.
Move validateInt32 and validateUint32 to this file.
PR-URL: https://github.com/nodejs/node/pull/19973
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: James M Snell <jasnell@gmail.com>
