sys: 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

sys: Remove $FreeBSD$: one-line .c pattern

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

libkern: clean up empty lines in .c and .h files

Remove inet_ntoa() from the kernel

inet_ntoa() cannot be used safely in a multithreaded environment
because it uses a static local buffer. Remove it from the kernel.

Suggested by: glebius, emaste
Reviewed by: gnn
MFC after: never
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D9625

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

- Import the HEAD csup code which is the basis for the cvsmode work.

/* -> /*- for copyright notices, minor format tweaks as necessary

Use __FBSDID().

add threadsafe version of inet_ntoa (inet_ntoa_r takes a buffer to fill)
this is used by some debugging functions

Add $FreeBSD$

Remove trailing whitespace.

Add inet_ntoa() and replace ARP's private routine with same.