Recognize LUN 0 device if SID_QUAL_LU_OFFLINE and T_NODEVICE are

Recognize LUN 0 device if SID_QUAL_LU_OFFLINE and T_NODEVICE are
true. This enables the discovery and probing of other LUNs the
target has to offer.

Add uk* to amd64 RAMDISK_CD so such devices are configured.

Allows bsd.rd as well as bsd[.mp] to boot on Oracle Cloud amd64
instances.

Issue reported by Ryan Kavanagh and Scott Nicholas via bugs@.

Original diff and much subsequent testing by Scott. Thanks!

ok dlg@ jmatthew@