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

Make systat(1) accept fractional number of seconds.
Make old alarm(3)-based code use select(2).

MFC after: 2 weeks

Whitespace fixes.

- Remove redundant empty lines.
- Replace ^L by \014. This allows you to safely cat/grep/etc this file
without causing confusion.

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

Revert most part of 200420 as requested, as more review and polish is
needed.

Remove unneeded header includes from usr.bin/ except contributed code.

Tested with: make universe

ANSIfy and remove register.

Resulting binary verified with strip(1)+md5(1).

Remove trailing whitespace.

Submitted by: Se=E1n Farley <sean-freebsd at farley dot org>
PR: bin/81874

Show the load average in the tcp display (it was already shown, perhaps
not very usefully, in all other displays). This was the original point
of the PR.

Move the load average up by 2 so that it starts in row 0 for all windows
(2 lines above it were wasted for all other windows except vmstat).
Move everything below it up by 2 or 3 (3 for icmp and icmp6 which had
an extra blank line due from not compensating for the foot-shooting in
note (3); only ip and ip6 compensated). Reduce the magic numbers related
to this.

Notes by the submitter:
%%%
1. All the subwin() calls are identical using #define MAINWIN_ROW 3
(systat.h).
2. The load average is at the top of the window.
3. Each display starts on the fourth line. I made changes to those
displays that shifted the start line (i.e., icmp). This entailed a
lot of changes within the comments at the top of those displays.
4. For ip6, I shifted the "Input next-header histogram" column down one
row to separate it from "IPv6 Output". I raised "bad scope packets"
and "address selection failed" up one row to stay with "IPv6 Input"
(valid?). They were down one row to probably line up at the bottom,
but I think they should stick with their fellow items in a column.
5. I condensed ifstat a bit. It had a lot of empty rows.
%%%

Submitted by: Se=E1n Farley <sean-freebsd at farley dot org>
PR: bin/81874

WARNS=2 fixes with NO_WERROR set, as there are some header issues
with namelists. use __FBSDID().

$Id$ -> $FreeBSD$

Add a mode to display ICMP statistics.

Inspired by: IRIX netstat -C