Reformat EFS on factory reset and shrink fs on failure to mount.

[sosthene-nitrokey]

Depends on :

• Add support for disabling block count check on mount and shrinking filesystems trussed-dev/littlefs2#103
• Update littlefs including shrinking and block count check flag trussed-dev/littlefs2-sys#27
• When factory-resetting the device, mark empty filesystems for reformatting trussed-dev/trussed-staging#36
• Prepare releases trussed-dev/trussed-staging#37

[nitrokey-ci]

No significant changes.

Insignifcant changes

metric	value		change
binary-size-nk3am	1,507,874	🔴	+2,057 (+0.14%)
binary-size-nk3am-test	1,876,537	🔴	+2,819 (+0.15%)
binary-size-nk3xn	540,464	🔴	+792 (+0.15%)
binary-size-nk3xn-test	540,544	🔴	+824 (+0.15%)
binary-size-nkpk	685,668	🔴	+2,446 (+0.36%)

[robin-nitrokey]

Needs to be updated to the new trussed-staging versions, otherwise LGTM.