2217's (reported by Matthew Jacob in NetBSD PR kern/6027) and Fujitsu
M2954's (reported by Tom Jackson).
Some of the Fujitsus at least hang when they get a cache sync command.
(Others just return illegal request.)
Also, make error printing in dashutdown() a little more selective. Don't
print any error when the sense key is illegal request. Drives that don't
support the synchronize cache command usually return illegal request.
Also, make sure the scsi status is check condition before going into
scsi_sense_print().
Reviewed by: gibbs
404d9ee9f6