Improve fstab parsing functionality

[DissectBot]

Currently, we support the following configurations:

/dev/mapper/
/dev/gpt/
/dev/../
UUID=

However, linux also has more types of mount options for an fstab file:

/dev/disk/by-partuuid/....
/dev/disk/by-path/...
/dev/disk/by-uuid/..

These currently generate warnings, which would be a nice add.