Comment 0 for bug 1597923

The mkfs.fat and mkfs.vfat tools do not by default permit the creation of a filesystem on a disk that has not been partitioned. This is not really a limitation of the filesystems themselves; it is just a safety feature to keep people from accidentally overwriting data.

Since some curtin users may have a need for whole disk fat/vfat filesystems, it makes sense to use the '-I' flag for mkfs.vfat commands, which forces the tools to work on whole disks. It appears that this flag does not interfere with any of the other options in mkfs, and so is essentially a force flag, and can just be added to family_flag_mappings in block.mkfs