MFC r314987-r314989, r314993-r314994, r315046-r315049, r315102

r314987:
Use nitems() from sys/param.h.

Reviewed by: asomers
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9944

r314988:
Use nitems() from sys/param.h.

Reviewed by: ume
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9938

r314989:
Use nitems() from sys/param.h and also remove the cast.

Reviewed by: markj
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9937

r314993:
Use nitems() from sys/param.h.

Reviewed by: ngie
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9936

r314994:
Use nitems() from sys/param.h.

Reviewed by: ngie
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9940

r315046:
Use nitems() from sys/param.h

Reviewed by: jhb
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9941

r315047:
Use nitems() from sys/param.h.

Reviewed by: np
MFC after: 3 weeks.
Differential Revision: https://reviews.freebsd.org/D9945

r315048:
Use nitems() from sys/param.h.

MFC after: 3 weeks.

r315049:
Bring back the cast removed in my previous commit to allow us build vmstat
with WARNS 2. This cast was first introduced at r87690.

Reported by: bde, pfg and ngie
MFC after: 3 weeks.

r315102:
Use nitems() from sys/param.h.

Reviewed by: ngie
Differential Revision: https://reviews.freebsd.org/D9943

MFC r310666,r310675:

r310666:

style(9) fixes

- Clean up trailing whitespace
- Fix variable type alignment in storage_OS_get_swap(..)

r310675:

Fix the build by moving the initializers for len/nswapdev down below the
declarations

Pointyhat to: ngie

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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

add zfs oid to bsnmpd

PR: bin/129360
Submitted by: Ulrich Spoerlein

Reduce the memory requirements for the tables by (1) using malloced strings
instead of maximum sized arrays embedded in the table structures and (2)
using pointers to constant oids instead of copying the oid into each
table structure. This also fixes indexing in the case when a string used
for indexing is longer than the maximum size allowed in the MIB.

Submitted by: Victor Cruceru <soc-victor@>

Forced commit because I lost the commit message in the previous commit:

This is the implementation of the HOSTRES MIB that was developed by
Victor during SoC 2005 with some stylification by philip@ and harti@.

Submitted by: Victor Cruceru <soc-victor@freebsd.org>
Reviewed by: philip, harti

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