nvmecontrol: Fix IEEE OUI Identifier output

Current sequence of IEEE OUI Identifier output is wrong.

For Intel, current output is e4 d2 5c, specification is 5CD2E4h
For Samsung, current output is 38 25 00, specification is 002538h
also check with Linux nvme-cli.

Reviewed by: imp, chuck
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D33856