Documentation: Move intelp2m from description.md to Documention

The description.md file for the intelp2m utility wasn't the description
that was needed - just a subject, and what language it was written in.
It was instead a set of more full documentation, so move it into the
Documentation directory and create a new description file.

Change-Id: Ia180ae41f91f8b8eb408351a9e44e899edc031d3
Signed-off-by: Martin Roth <gaumless@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64578
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <felixsinger@posteo.net>

Documentation/util.md

@@ -157,6 +157,7 @@ the documentation `Bash`
 
 * [cbfstool](util/cbfstool/index.md)
 * [ifdtool](util/ifdtool/index.md)
+* [intelp2m](util/intelp2m/index.md)
 
 ## Generated documentation