Add public interfaces for accessing builtin package info (Bug#78844)

Add public interfaces for accessing builtin package info (Bug#78844)

The following upstream patch has been backported:

  Add public interfaces for accessing builtin package info (Bug#78844)

  * lisp/emacs-lisp/package.el (package-builtin-packages)
  (package-builtin-package-version): New functions.
  * doc/lispref/package.texi: Add a section 'Package Information' with
  documentation for the new functions.
  * etc/NEWS: Add entry for 'package-versioned-builtin-packages' and
  'package-builtin-package-version'.

Origin: upstream, commit 5c75ec6ae52a5b06ad0424ce805f5ea0432b6e90
Forwarded: not-needed