tools: 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/

Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Update most userspace consumers of capability.h to use capsicum.h instead.

auditdistd is not updated as I will make the change upstream and then do a
vendor import sometime in the next week or two.

MFC after: 3 weeks

Fix order of arguments to lseek().

PR: 160867
Submitted by: Henning Petersen <henning.petersen@t-online.de>
MFC after: 1 week

Flesh out the cap_test regression test.

Add more regression testing, some of which is expected to fail until we
commit more kernel implementation.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc

Regression tests for Capsicum capability mode.

Ensure that system calls that access global namespaces, e.g. open(2), are not permitted, and that whitelisted sysctls like kern.osreldate are.

Approved by: rwatson
Sponsored by: Google, Inc.