wasi: update to latest commit past sdk-22

devel/wasi-libc is now flavourised per supported LLVM version. Each
flavour includes/copies the corresponding clang's stdarg.h and
stddef.h instead of simply using the latest clang release.

Technically upstream dropped support for LLVM < 18, but the commit
doing so admittedly operated under an uncertain assumption. LLVM
17 is still supported in these ports for the benefit of Rust and
gecko@ ports, which specify LLVM 17 minimum, and to facilitate LTO
with that version. LLVM 19 is also supported in this version, with
the corresponding ports to be committed separately.

Bump PORTREVISION of consumers

wasi: drop support for LLVM < 17

Prepare for update

devel/wasi-libc: refresh std{arg,def} headers from LLVM 18

cleanup: (ir)regular GH_TAGNAME cleanup

devel/wasi-libc: update to sdk-21

Bump PORTREVISION of consumers

wasi: update libc to sdk-20 and modularise LLVM bits

wasi-libcxx and wasi-compiler-rt now meta ports (similar to u-boot);
the build process is the same for each LLVM version so child ports
are minimal. Minimum supported LLVM version is 12, thus its
corresponding child ports are resurrected and LLVM 11 child ports
are removed.

Since all supported LLVM versions are made available at once, remove
restriction in bsd.gecko.mk and switch to USES=llvm throughout. LTO
on gecko ports should now work with later LLVM versions so long as
${DEFAULT_VERSIONS} is set properly and matches the LLVM used in
rust (if not using the PORT_LLVM option).

Reviewed by: brooks (LLVM ports interactions)
Tested by: Eric Camachat <eric[at]camachat[dot]org>
Approved by: maintainer timeout (gecko@ portion, 2+ weeks)
PR: 274896
Differential Revision: https://reviews.freebsd.org/D40098

devel/wasi-*: take maintainership

These have to be coordinated with gecko@.

Approved by: mentors (implicit)

*/*: Release ports from maintainership

Maintainer releases all his ports.

PR:		266871
Reported by:	unrelentingtech <greg@unrelenting.technology>

Remove WWW entries moved into port Makefiles

Commit b7f05445c00f has added WWW entries to port Makefiles based on
WWW: lines in pkg-descr files.

This commit removes the WWW: lines of moved-over URLs from these
pkg-descr files.

Approved by:		portmgr (tcberner)

Add WWW entries to port Makefiles

It has been common practice to have one or more URLs at the end of the
ports' pkg-descr files, one per line and prefixed with "WWW:". These
URLs should point at a project website or other relevant resources.

Access to these URLs required processing of the pkg-descr files, and
they have often become stale over time. If more than one such URL was
present in a pkg-descr file, only the first one was tarnsfered into
the port INDEX, but for many ports only the last line did contain the
port specific URL to further information.

There have been several proposals to make a project URL available as
a macro in the ports' Makefiles, over time.

devel/wasi-libc: Update to g20210923.

Differential Revision:	https://reviews.freebsd.org/D32440

One more small cleanup, forgotten yesterday.
Reported by:	lwhsu

Remove # $FreeBSD$ from Makefiles.

devel/wasi-compiler-rt11, wasi-libc, wasi-libcxx: New ports for WebAssembly
System Interface (WASI) libc, clang builtins (compiler-rt), libc++, libcxxabi

WASI is a "syscall" interface for WebAssembly, significantly inspired by
CloudABI.
It is supported in clang 8 and up, but to actually build C programs,
it needs clang builtins and the libc/sysroot. And for C++, also libc++ and
libcxxabi.

Submitted by:		Greg V <greg%unrelenting.technology>
Differential Revision:	https://reviews.freebsd.org/D22960