For LUKS2 headers with non zero data offset LUKS2_wipe_header_areas
will always erase the smallest from following:

- metadata device size
- data offset value
- maximal LUKS2 metadata size (twice 2 MiBs json area including 128 MiB for
binary keyslot areas) even with detached header.

For zero value data offset (LUKS2 header can not be restored back to
data device), we erase up to smallest from the following values:

- metadata device size
- maximal LUKS2 metadata size (twice 2 MiBs json area including 128 MiB for