grub2 was updated to fix various bugs just before release:
- efi_libdir = _libdir = /usr/lib
- package /usr/lib/grub2 dir only once
- move grub.efi to /usr/lib/grub2/%{grubefiarch}/
- create a symlink so that scripts can find it there.

- merge internal+external BS changes into superset spec file,
remove obsolete dependencies
- merge SLES+openSUSE patches, restrict "grub-efi" to 12.2
- add efidisk-ahci-workaround (bnc#794674)
- fix unquoted-string-in-class.patch (bnc#788322)