MBR table handling

[bluecmd]

Implement loading (and reading?) the MBR table.

For an example, see https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_Opal_SSC_Application_Note_1-00_1-00-Final.pdf - "3.2.9.3 Set the MBR table"

[bluecmd]

Note that this might need the "Namespace for MBR Shadow" feature as well.

[bluecmd]

Reading MBR has been implemented

[ChriMarMe]

I cant tell if this issue is solved or if there is stuff left to do @bluecmd . Can you tell me?

[bluecmd]

@ChriMarMe I seem to recall that namespaces for MBR shadowing is still left to be decided on