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 r258311

  opensolaris/uts/common/dtrace/fasttrap.c
          Fix several problems that can cause panics on kldload and kldunload.

          * kproc_create(fasttrap_pid_cleanup_cb, ...) gets called before
            fasttrap_provs.fth_table gets allocated.  This can lead to a panic
            on module load, because fasttrap_pid_cleanup_cb references
            fasttrap_provs.fth_table.  Move kproc_create down after the point
            that fasttrap_provs.fth_table gets allocated, and modify the error
            handling accordingly.

          * dtrace_fasttrap_{fork,exec,exit} weren't getting NULLed until
            after fasttrap_provs.fth_table got freed.  That caused panics on
            module unload because fasttrap_exec_exit calls
            fasttrap_provider_retire, which references
            fasttrap_provs.fth_table.  NULL those function pointers earlier.

          * There wasn't any code to destroy the
            fasttrap_{tpoints,provs,procs}.fth_table mutexes on module unload,
            leading to a resource leak when WITNESS is enabled.  Destroy those
            mutexes during fasttrap_unload().

Sponsored by: Spectra Logic Corporation

(cherry picked from commit af2e55ef73071fef28a1ea9377c150376c06a737)
MFC r227294: SDT's struct sdt_argtype can be marked static everywhere

MFC slacker:	ed

(cherry picked from commit 2849902f5ffbe4699605630d6c3010c86c473bbd)
MFC r250816:

Protect SDT_PROBE() with do { } while (0) loop.

(cherry picked from commit 9c7cd11f16b5ab9294daa82f2f0ea405b615d411)
MFC r252895: Add a man page for the SDT_* macros

(cherry picked from commit f25b5e7d33fcae8f270d771f5aa05fa68834d275)
MFC r254468,r254469: Add a "translated type" argument to SDT_PROBE_ARGTYPE()

Note: this breaks ABI compatibility with older modules with SDT probes.

My opinion is that benefits outweigh downsides, because I am not aware
of any thirdparty binary-only modules with SDT probes.

(cherry picked from commit 309c524ba7bf76f96c42ee41d970460eb09835d0)
MFC r254810: Remove the kld lock macros and just use the sx(9) API

(cherry picked from commit 4f3cfb5604366717ad737f0ed51684eb22f2265e)
MFC r254811: call linker_file_lookup_set() with the shared lock held

(cherry picked from commit 843f1d4e1d17296293375b49ee4538c168b0188a)
MFC r255776: Give argtype struct names a different prefix than probe
struct names

(cherry picked from commit 677bec45acfb6de80fd858dd1afe09e392ab35e9)
MFC r255777: Omit "__restrict" when generating syscall argument strings

syscall argument strings are also regenerated as part of this commit

(cherry picked from commit 441c4aa7aced083c6126e0bd68b20ccd32d16a15)
MFC r257143: Fix a couple of bugs in the fasttrap emulation of a "push
%rbp" instruction

(cherry picked from commit da83a01685d10c3a548afb067c2d88b1a244c3d6)
MFC r254266,254309: Add event handlers for module load and unload events

This is just a merge of EVENTHANDLER.9, the actual code chnage was merged earlier.

(cherry picked from commit 0af0768071a0ed8ba45af89abff6f53d4554b8e0)
MFC r254813,259587: Rename the kld_unload event handler to kld_unload_try

(cherry picked from commit 732ce6a99e3edee4ff47a4825d2923edb1f45f3c)
MFC r257152: Do some cleanup of the SDT code

(cherry picked from commit bdcae7d007bff18e5b105dc2b53960f2486108ab)
MFC r257417:  Remove references to an unused fasttrap probe hook

(cherry picked from commit 1007b3d41e1e3819ac3f016cf28053a6504036d4)
MFC r257679: Use suword32 and suword64 instead of copyout(9) in fasttrap

(cherry picked from commit 808d50ebfda5ee2c359c5b71596568abf6800284)
MFC r258291: change the ioctl definition so that the fasttrap ioctl
handler is responsible for copying in userland data

(cherry picked from commit aa0506a8bcd20ca6fefed9927636a1c6d433a30c)
MFC r252850: Hide references to mod_lock

(cherry picked from commit c1c5e2c822f05d6d6325677f5a44dc3f39c59575)