MFC r326937, r326940 (by imp):
When we're disabling the nvme device, some drives have a controller
bug that requires 'hands off' for a period of time (2.3s) before we
check the RDY bit. Sicne this is a very odd quirk for a very limited
selection of drives, do this as a quirk. This prevented a successful
reset of the card when the card wedged.

Also, make sure that we comply with the advice from section 3.1.5 of
the 1.3 spec says that transitioning CC.EN from 0 to 1 when CSTS.RDY
is 1 or transitioning CC.EN from 1 to 0 when CSTS.RDY is 0 "has
undefined results". Short circuit when EN == RDY == desired state.

Finally, fail the reset if the disable fails. This will lead to a
failed device, which is what we want. (note: nda device needs
work for coping with a failed device).