Disable copy-on-write for /home

[NeroReflex]

The rest of the system benefits from copy-on-write: snapshot that are restored (and can be checked) by frzr, compression that got enabled at creation-time, file checksums to ensure integrity.

/home and /var do not benefit from CoW however, they might host frequently-written files, potentially even a VM disk: disable CoW for /home so that it can be mounted without nodatacow.