Comment 0 for bug 1926748

[Impact]

 * regression in xenial updates - grub2 cannot handle new relocations

 * grub-efi-arm64-bin gained new recommends on -signed package which is attempted to be installed

 * it pulls in one grub which was built with a newer toolchain and has more relocations

 * non-secureboot grub-install in xenial fails to install it when creating core.efi, because it does not know how to handle new relocations.

[Test Plan]

 * install new grub2-common grub-common

 * install grub-efi-arm64-signed from xenial-updates

 * package installation should be successful

 * this is executed as part of autopkgtest upgrades when testing any package on xenial in our autopkgtest cloud

[Where problems could occur]

 * we are rebuilding grub2 which will have to go into security pocket eventually. Thus it's best to rebuild grub2 in security pocket.