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