Recent releases of redhat grub2 will always fail when installing to
EFI paths, to encourage a transition to the signed shim bootloader.
Partition image deploys avoid calling grub2-install with the
preserve-efi-assets functions. Deploying whole disk images doesn't
require grub2-install. This leaves whole disk images installed onto
softraid devices, which still attempts to call grub2-install.
This change will still attempt to run grub2-install in this
one remaining case, but will ignore any failure.
A future enhancement can avoid calling grub2-install entirely so that
non-redhat secure-boot capable images can keep their signed
bootloaders.
Story: 2008923
Task: 42521
Change-Id: If432ef795d64d76442d739eb4f7d155ff847041e