uefi: Add erase and getvar support

fastboot format userdata now works with these 2 patches:
https://github.com/96boards-hikey/edk2/commit/5f4e3dcabe819564c1c51231a1906541d773600b
https://github.com/96boards-hikey/edk2/commit/e84cb79e409b87f9df0e83cab16b9f052e123183

Change-Id: I5c97aec390adf7965552aba9c83d79a30b8f2d82
Signed-off-by: Vishal Bhoj <vishal.bhoj@linaro.org>
3 files changed