mkefidisk.sh: Add script to do an EFI install on the host

mkefidisk.sh: Add script to do an EFI install on the host

Sometimes it is convenient to prepare a bootable image from the
host rather than using a live-image to install to a disk on the
target.

This script takes a live image as input, partitions a device, and
performs the installation just as the installer would if run on
the target.

(From OE-Core rev: 7225c6739f9f1e51741a42437692868165aa1dfe)

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>