handbook/basics/disk-organization: add nvme disk names

Add nvme disk names (nda, nvd), remove obsolete 'ad', 'acd', 'ast',
'mcd' and 'scd' device names. Did not remove raid adapters gone in 13,
but still present in 12.

Note: this section needs a refresh to move from MBR slice and disklabel
to GPT slices.

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