CTL: Increase maximum SCSI tag size from 32 to 64 bits.
SAM-5 specification states maximum size of command identifier (tag),
defined by specific transports, should not be larger than 64 bits.
While most of supported transports use 32 bits or less, it was
reported that virtio-scsi uses 64 bits. Truncation to 32 bits in
bhyve code caused false tag conflict errors reported and possibly
other issues.
This changes CTL ABI and HA protocol, so CTL_HA_VERSION is bumped.
While we make HA protocol incompatible, increase default maximum
number of ports in CTL from 256 to 1024, matching number of LUNs.
There are many reports from people who need many iSCSI targets with
only one LUN each. Increased memory consumption should be less of
a problem these days.