lightnvm: add mccap support

lightnvm: add mccap support

BugLink: http://bugs.launchpad.net/bugs/1531539
Some flash media has extended capabilities, such as programming SLC
pages on MLC/TLC flash, erase/program suspend, scramble and encryption.
MCCAP is introduced to detect support for these capabilities in the
command set.

Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
(cherry picked from commit f9a9995072904f2d67d649545f17f81e00f4985e)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>