Add reading Opal NVMe encryption information

Add reading Opal NVMe encryption information

For NVMe devices with Opal support, encryption information, status and
ability are determined based on Opal Level 0 discovery response. Technical
documentation used is given in the implementation.

Ability in general describes what type of encryption is supported, Status
describes in what state the disk with encryption support is. The current
patch includes only the implementation of reading encryption information,
functions will be used in one of the next patches.

Motivation for adding this functionality is to block mixing of disks in
IMSM arrays with encryption enabled and disabled. The main goal is to not
allow stealing data by rebuilding array to not encrypted drive which can be
read elsewhere.

Value ENA_OTHER from enum encryption_ability will be used in the next
patch.

Signed-off-by: Blazej Kucman <blazej.kucman@intel.com>
Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com>