efi: Prefer shim image loader protocol if it exists
shim has all the facilities to load and authenticate PE images against
MOK or the system firmware's cert store, but only exposes its
verification routine via the shim lock protocol, leaving it to loaders
such as GRUB to implement PE loading from scratch when booting Linux via
its EFI stub.
Now that shim exposes load/startimage equivalents, let's use these and
boot in EFI mode in cases where shim is active.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2 files changed
