MFC r319897-r319898, r319904: Improve yes' throughput

r319897: Improve yes' throughput

On my system, this brings up the throughput from ~20 to ~600 MiB/s.

Inspired by:
https://www.reddit.com/r/unix/comments/6gxduc/how_is_gnu_yes_so_fast/

r319898: Handle partial writes

r319904: style(9) fixes.

MFC r308432, r308657: Capsicumize some trivial stdio programs

r308432: Capsicumize some trivial stdio programs

Trivially capsicumize some simple programs that just interact with
stdio. This list of programs uses 'pledge("stdio")' in OpenBSD.

r308657: fold(1): Revert incorrect r308432

As Jean-Sébastien notes, fold(1) requires handling argv-supplied files. That
will require a slightly more sophisticated approach.

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

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

Remove the advertising clause from UCB copyrighted files in usr.bin. This
is in accordance with the information provided at
ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change

Also add $FreeBSD$ to a few files to keep svn happy.

Discussed with: imp, rwatson

#include <err.h> to make yes warns clean again.

Detect and exit on write errors.

ANSIify function definitions.
Add some constness to avoid some warnings.
Remove use register keyword.
Deal with missing/unneeded extern/prototypes.
Some minor type changes/casts to avoid warnings.

Reviewed by: md5

Silence warnings.

This commit was generated by cvs2svn to compensate for changes in r1590,
which included commits to RCS files with non-trunk default branches.

BSD 4.4 Lite Usr.bin Sources