virtio_blk: Add support for lifetime feature

virtio_blk: Add support for lifetime feature

The VirtIO TC has adopted a new feature in virtio-blk enabling
discovery of lifetime information.

This commit adds support for the VIRTIO_BLK_T_LIFETIME command
to the virtio_blk driver, and adds two new attributes to the
sysfs entry for virtio_blk:
* pre_eol_info
* life_time

which are defined in the same manner as the files of the same name
for the eMMC driver, in line with the VirtIO specification.

Signed-off-by: Enrico Granata <egranata@google.com>
Link: https://lore.kernel.org/r/20210330231602.1223216-1-egranata@google.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>