Provide 4M OVMF images for Focal
The existing 2MB images no longer have sufficient variable space for the current Secure Boot Forbidden Signature Database. LP: #1885662.
Update fw descriptors to reference 4M images instead of their 2M counterparts. This will migrate tools that use the descriptor interface (like libvirt) over to the 4M images when creating new VMs. Existing 2M VMs will require manual migration.
Cherry-picked-from: https://salsa.debian.org/qemu-team/edk2/-/commits/debian/2020.05-3/
Fixes: https://bugs.launchpad.net/ubuntu/+source/edk2/+bug/1885662
SRU paperwork: https://bugs.launchpad.net/ubuntu/+source/edk2/+bug/1995930
Edited by Mustafa Kemal GILOR