bhyve nvme: Fix Set Features, AEN

NVMe Controllers which do not support Endurance Groups must return an
error when the Endurance Group Event Aggregate Log Change Notices bit is
set in Set Features, Asynchronous Event Configuration.

Fixes UNH IOL Test 3.12, Case 8

Tested by: jason@tubnor.net
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D33577