meta-arm: Add UEFI EDK2 support for Arm platforms

EDK2 Project is a modern, feature-rich, cross-platform
firmware development environment for the UEFI specifications
from www.uefi.org.

This patch adds a new recipe to fetch, configure and build
UEFI EDK2 firmware for Arm platforms.

Change-Id: Icfb157e5b68d87accfd4290f522fc529fe4e849e
Issue-Id: PLATFORMS-3134
Signed-off-by: Khasim Syed Mohammed <khasim.mohammed@arm.com>
Reviewed-by: Diego Sueiro <diego.sueiro@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>