pcr: libreboot-util: rename to libreboot-utils and fix header
Since there is more than one utility in this package it's
more clear if it is named libreboot-utils.
In addition, this packages has part from the nvramtool I made
from scratch so I added myself in the header in addition of
Wael Karramas who is the main author of this package.
I also fixed the Maintainers line as more than one person involved in
Parabola has some knowledge about Libreboot and Coreboot.
Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>