Fix ctld crash on startup if target alias is not set.

MFC after:	3 days

(cherry picked from commit e0b7e1e4572c3be1755009390ed8983b20b069e7)
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 even need it.

MFC after:	2 weeks

(cherry picked from commit b324b7bdb5795179d4a19f90251bb9e4cf9029e1)
Increase maximal number of SCSI ports in CTL from 32 to 128.

After I gave each iSCSI target its own port, the old limit appeared to be
not so big.  This change almost proportionally increases per-LUN memory
use, but it is still three times better then it was before r268807.

MFC after:	2 weeks

(cherry picked from commit c253b272de56534871290ca33584d683c8cfa16d)
MFC r258294:
Fix ZFS deadlock when sending a snapshot which is mounted.

Approved by:	re (glebius)
Sponsored by:	Multiplay
Starting lockd and statd before DAEMON is not required
Intel S3700 SSD quirks
ata_da: handle ATA_SF_ENAB_WCACHE
ZFS/GFS handling fixes
Applied http://people.freebsd.org/~avg/l2arc-b_tmp_cdata-diag.2.patch
Disabled arc_event_lowmem vm_lowmem handler