usr.bin: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

systat: Eliminate write-only unit variable

Sponsored by: Netflix

systat: mostly clean up warns

Sponsored by: Rubicon Communications, LLC ("Netgate")

Augment systat(1) -swap to display large swap space processes

This change updates the systat(1) -swap display to use libprocstat to
obtain and display per-process swap space usage infomation following its
existing swap devise/file statistics. It also incorporates the disk I/O
information from the -vmstat display.

The new screen looks like below with 'systat -swap':
/0 /1 /2 /3 /4 /5 /6 /7 /8 /9 /10
Load Average |

Device/Path Size Used |0% /10 /20 /30 /40 / 60\ 70\ 80\ 90\ 100|
ada0s1b 2048M 2034M
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
zvol/sys/tempora 1024M 1015M
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
zvol/sys/swap 1024M 1014M
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Total 4096M 4063M
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Pid Username Command Swap/Total Per-Process Per-System
24153 hiro seamonkey 98M / 1G 7% 2%
23677 hiro xfce4-pane 28M / 81M 34% XXX 0%
23629 hiro xfce4-sess 25M / 118M 21% XX 0%
23681 hiro xfdesktop 20M / 58M 34% XXX 0%
23678 hiro thunar 15M / 43M 36% XXX 0%
23658 hiro at-spi-bus 14M / 23M 63% XXXXXX 0%
23660 hiro gvfsd 12M / 21M 56% XXXXX 0%

Disks ada0 ada1 ada2 cd0 pass0 pass1 pass2 pass3
KB/t 8.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
tps 0 0 0 0 1 0 0 0
MB/s 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
%busy 0 0 0 0 0 0 0 0

Submitted by: Yoshihiro Ota
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29754

Clean up copyright messages.

Reported by: Yoshihiro Ota
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D29354

Improve size readability.
Preserve more space for swap devise names.
Prevent line overflow with long devise name.
Don't draw a bar when swap is not used at all.
Simplify and optimize code.
Change the label to end at end of 100%.
PR: 251655
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D27496

Introduce sysputpage() to display large page size with human readable format.
Using UI units allows to fit larger numbers in columns.
Stop calling v_page_size - this is a value that doesn't change at runtime.
Renamed WINDOW *wnd to *wd to avoid conflict with global *wnd variable.
Use bit-shift to convert page size to byte.

PR: 246458
Submitted by: ota@j.email.ne.jp
MFC after: 2 weeks
Differential Revision: D24834

Add missing sysput.c

PR: 237664
Submitted by: ota@j.email.ne.jp
Reported by: imb, cy