MFC r269149:
Fix several cases of NULL dereference when INQUIRY sent to absent LUN.
MFC r268581:
Merge several equal serialization indexes.
MFC r268767:
Add support for VMWare dialect of EXTENDED COPY command, aka VAAI Clone.

This allows to clone VMs and move them between LUNs inside one storage
host without generating extra network traffic to the initiator and back,
and without being limited by network bandwidth.

LUNs participating in copy operation should have UNIQUE NAA or EUI IDs set.
For LUNs without these IDs VMWare will use traditional copy operations.

Beware: the above LUN IDs explicitly set to values non-unique from the VM
cluster point of view may cause data corruption if wrong LUN is addressed!

Sponsored by:	iXsystems, Inc.
MFC r268807:
Reduce per-LUN memory usage from 18MB to 1.8MB.

CTL never had use for CA support code since SPI has gone, and there is no
even frontends supporting that.  But it still was reserving 256 bytes of
memory per LUN per every possible initiator on every possible port.

Wrap unused code with ifdef's in case somebody ever need it.