Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r249426;

Merge change from illumos:

3519 DTrace fails to resolve const types from fbt
3520 dtrace internal error -- token type 316 is not a valid D
compilation token
3521 clean up dtrace unit tests

Illumos Revision: e98f46c

Reference:
https://www.illumos.org/issues/3519
https://www.illumos.org/issues/3520
https://www.illumos.org/issues/3521

Tested by: Fabian Keil
Obtained from: Illumos

MFC r248690, r248706, 248708, r248752:
Dtrace: merge new functions from Illumos.

This covers illumos issues:

1455 DTrace tracemem() should take an optional size argument
1451 DTrace needs toupper()/tolower() subroutines
1457 lltostr() D subroutine should take an optional base
1694 Add type-aware print() action
3511 dtrace.c erroneously checks for memory alignment on amd64

This includes an enhanced print() described here:

http://dtrace.org/blogs/eschrock/2011/10/26/your-mdb-fell-into-my-dtrace/

This change bumps the DT_VERS_* number to 1.9.0 in
accordance to what is done in illumos.

Illumos Revisions: 13457:571b0355c2e3
13458:5e394d8db762
13459:c3454574dd1a
13501:c3a7090dbc16
13483:f413e6c5d297

Reference:
https://www.illumos.org/issues/1455
https://www.illumos.org/issues/1451
https://www.illumos.org/issues/1457
https://www.illumos.org/issues/1560
https://www.illumos.org/issues/1694
https://www.illumos.org/issues/3511

Tested by: Fabian Keil
Obtained from: Illumos

Dtrace: Add SUN MDB-like type-aware print() action.

Merge change from illumos:

1694 Add type-aware print() action

This is a very nice feature implemented in upstream Dtrace.
A complete description is available here:
http://dtrace.org/blogs/eschrock/2011/10/26/your-mdb-fell-into-my-dtrace/

This change bumps the DT_VERS_* number to 1.9.0 in
accordance to what is done in illumos.

While here also include some minor cleanups to ease further merging
and appease clang with a fix by Fabian Keil.

Illumos Revisions: 13501:c3a7090dbc16
13483:f413e6c5d297

Reference:
https://www.illumos.org/issues/1560
https://www.illumos.org/issues/1694

Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 1 month

Tag vendor/illumos/dist as 20120614 (illumos-gate 13742:b6bbdd77139c)

Update vendor/illumos/dist to pre libzfs_core state (dtrace and ctf part)
illumos-gate revision 13742:b6bbdd77139c

Obtained from: ssh://anonhg@hg.illumos.org/illumos-gate