fix: efi fat32 compatibility with nvme 4KBn sector size

[aarnaud]

Pull Request

What? (description)

Fix the compatibility For Advanced Format 4K Native drives (4-KB-per-sector) drives, the minimum size is 260 MB, due to a limitation of the FAT32 file format.

Why? (reasoning)

FAT32 spec :

• https://github.com/dosfstools/dosfstools/blob/master/src/mkfs.fat.c#L125
• https://www.cs.fsu.edu/~cop4610t/assignments/project3/spec/fatspec.pdf
• https://superuser.com/questions/1702331/what-is-the-minimum-size-of-a-4k-native-partition-when-formatted-with-fat32
• https://bbs.archlinux.org/viewtopic.php?id=168014

Acceptance

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• you linked an issue (if applicable)
• you included tests (if applicable)
• you ran conformance (make conformance)
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• you linted your code (make lint)
• you generated documentation (make docs)
• you ran unit-tests (make unit-tests)

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[smira]

Thanks for your PR, it does make a lot of sense. We need to consider on our side the effects of changing size of the partition for existing installs (when upgrading). It makes perfect sense for upgrades of course.

[frezbo]

Thanks for your PR, it does make a lot of sense. We need to consider on our side the effects of changing size of the partition for existing installs (when upgrading). It makes perfect sense for upgrades of course.

while we move to sd-boot for 1.7 we can maybe make it bigger to accomodate UKI too? 🤔

[smira]

If we move to sd-boot, we have 1 GiB EFI partition there. This change is about GRUB-style partitioning scheme.