lib/msun: Cleanup after $FreeBSD$ removal

Remove no longer needed explicit inclusion of sys/cdefs.h.

PR: 276669
MFC after: 1 week

Remove $FreeBSD$: one-line .c pattern

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

Fix a bug where the wrong argument was passed to SET_FLOAT_WORD().
This bug results in a type mismatch that happens to be harmless
because of the way SET_FLOAT_WORD() works.

Submitted by: bde

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

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

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

s/rcsid/__FBSDID/

Implement nexttowardf. This is used on both platforms with 11-bit
exponents and platforms with 15-bit exponents for long doubles.