gnu-efi: upgraded package to upstream

Upgraded sys-boot/gnu-efi to 3.0.12

shim 15 requires gnu-efi 3.0.8 or later.

There is additional step in src_prepare that copies a license file from
README.efilib to LICENSE to make chromiumos license checker happy.

BUG=b/179529890
TEST=presubmit
RELEASE_NOTE=None

Change-Id: Id6c8eb14a45a759c4d4ce4514cc7d2bdeb14bf67
Reviewed-on: https://cos-review.googlesource.com/c/third_party/overlays/portage-stable/+/13952
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Reviewed-by: Roy Yang <royyang@google.com>
4 files changed