MFC r255878:
  Now that the portsnap buildbox is generating the raw bits for INDEX-10,
  add it to the set of INDEX files built by portsnap.
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 233422,233680,233681,237619,239904,249373,252346,252379,252423:
Sync locking(9) with HEAD.  The only change not merged is that 9 still
supports !MPSAFE filesystems.
MFC	r254941;

Merge a couple of CTF fixes from illumos:

2942 CTF tools need to handle files which legitimately lack data
2978 ctfconvert still needs to ignore legitimately dataless files on SPARC

Illumos Revisions:	13745:6b3106b4250f
			13754:7231b684c18b

Reference:

https://www.illumos.org/issues/2942
https://www.illumos.org/issues/2978

Obtained from:	Illumos