nvme: Timeout expired transactions

When we went to having a shared timeout routine, failing the timed-out
transaction code was inadvertantly dropped. Reinstate it.

Fixes: 502dc84a8b670
Sponsored by: Netflix
MFC After: 2 weeks
Reviewed by: chuck, jhb
Differential Revision: https://reviews.freebsd.org/D36921

(cherry picked from commit 2a6b7055a980f7e7543dfdbda4aa0c356133b77d)
(cherry picked from commit a276199fef37b04b8b3678eab90f0c33095a6c4d)

Approved-by: re (cperciva)