Pull request for UEFI sub-system for v2019.07-rc1
The patch series adds support for the BootNext and BootCurrent variables.
The rest is mostly bug fixes. With the bug fixes in place it becomes
possible to use the EFI Shell `edit` command.
A new unit test is supplied to check the image base and size fields of the
loaded image protocol.
An inline check when freeing memory from the pool safeguards against double
frees.