nvme: do not complete a command when its Abort is not performed

[seuros]

Summary

An Abort completion with cdw0 bit 0 set means the controller did not
abort the command; the command can still complete later. The driver
treated this as aborted anyway: it completed the command itself and
freed the CID. When the controller completed the command later,
the CID may already belong to a new command, so the new command
finished with the old command's status, or the unknown-cid assertion
fired on INVARIANTS kernels. The watchdog also kept sending a new
Abort for the same command every half second while the first one was
still pending.

[imp]

Aborting isn't on by default, so we have few miles on that code....

Does the watchdog we have for resetting the controller need to change because of this?

[seuros]

This diff implement it , the watchdog change is already here.

There is only one scenario missing if the Abort succeeds but the controller never posts the original command's completion, abort_state stays SENT forever.

I will add it in a followup diff as i finishing mapping the state machine from the spec.

[imp]

This is OK, but contingent on the followup.