[PATCHv2] NVMe: Async event request

[Keith Busch]

Scratch this ... it loses count on a suspend/resume or reset.

On Wed, 18 Jun 2014, Keith Busch wrote:
> Submits NVMe asynchronous event requests, one event up to the controller
> maximum or number of possible different event types (8), whichever is
> smaller. Events successfully returned by the controller are logged.
>
> Signed-off-by: Keith Busch <keith.busch at intel.com>