MFC r239710 (by glebius):
Fix function name in keg_cachespread_init() assert.
MFC r240676 (by glebius):
If caller specifies UMA_ZONE_OFFPAGE explicitly, then do not waste memory
in an allocation for a slab.
MFC r246087 (by glebius):
Fix typo in debug printf.
MFC r257805, r257806, r257807:

r257805:
  Add a 'mini-memstick.img' release target, which will use the
  'bootonly.iso' components to create a smaller memory stick image.

  This is useful for system recovery, where a full memstick.img image
  is not necessarily needed (or wanted).  In addition, it is possible to
  do bootonly-style installation, where the base.txz, kernel.txz, etc.
  are fetched from a remote source.

  Provide backwards-compatible target (mini-memstick), to keep in sync
  with the targets documented in release/Makefile.

r257806:
  Remove extra target from 'memstick' in r257805.

r257807:
  Update release(7) to include 'mini-memstick' target.

Sponsored by:	The FreeBSD Foundation
MFC r257942, r258101:

r257942:
  Fix a few style nits.

r258101:
  Since the doc/ toolchain conversion to docbook 5.0, JADETEX
  is no longer a valid option, so remove 'WITHOUT_JADETEX=yes'
  from PBUILD_FLAGS.

  While here, also remove 'WITHOUT_X11=yes', since it will
  cause a dependency conflict by requiring both print/ghostscript9
  and print/ghostscript9-nox11.

  Switch to OPTIONSNG format (WITHOUT_* -> OPTIONS_UNSET='FOO'),
  and unset the FOP option, which requires Java (although it is
  disabled by default).  Also unset the 'IGOR' option, since
  textproc/igor is a validation tool, not necessarily a dependency
  of the doc/ build itself.

  While here, reduce the line length of PBUILD_FLAGS.

Sponsored by:	The FreeBSD Foundation
MFC r257874:

Fix extattr(2) MLINKS.
MFC 226145,226147,226148,226150,226151,226153,226157,226158,226164,226246,
226262,226329,226344,226608:
Merge most "infrastructure" changes to kdump to make other MFC's to add
new decodings, etc. easier:
- Some of the #defines or enums for which we auto-generate naming
  functions may be wider than int, so use intmax_t throughout.
- Auto-generate kdump_subr.h.
- Use a switch statement instead of a giant if-else.
- Remove a lot of (void) casts.
- Bring ioctlname() in line with all the other *name() functions, which
  actually print the name (or the numeric value, if they can't figure out
  the correct name) instead of just returning a pointer to it.  Also, since
  ioctl numbers are not and probably never will be unique, drop support for
  using a switch statement instead of an if/else chain.
- Mostly WARNS=6 clean.
- Update mkioctls to still work with both kdump and truss.
libcpp: Keep a record of changes from upstream GCC (pre-43).

This makes it easier to track the changes in the rare event of the code
being distributed without access to version control.

MFC after:	3 weeks
Revert r258528: wrong tree

Inofensive as it is, this was meant for current. It will be re-merged
along with related changes in 3 weeks.