K 10
svn:author
V 3
dim
K 8
svn:date
V 27
2021-12-25T11:56:59.497678Z
K 7
svn:log
V 540
Add C++ headers <barrier> <concepts> <execution> <latch> <numbers> <semaphore>

I missed adding these to the libc++ Makefile, when importing
llvm-project 11.0.0-rc1, even though they were supplied by upstream.

While here, update OptionalObsoleteFiles.inc to add these new headers,
and cleanup old cruft.

Reported by:	yuri
Submitted by:	jkim (Makefile diff)
PR:		255374
MFC after:	3 days

(cherry picked from commit 95aa617e4bf09fcc813b1bab3d0dbf4b606807b1)

Git Hash:   761122c601e849229191a097a5741eda3ab1edb4
Git Author: dim@FreeBSD.org
END