As of
https://chromium-review.googlesource.com/c/chromium/tools/build/+/2586225,
we no longer test on Yasm. Yasm hasn't seen a release for over six years
now and is missing support for newer x86 instructions.
This removes the remnants of support for Yasm on the CI. It also removes
the Yasm support we patched into x86nasm.pl, which removes a now
unnecessary divergence from upstream.
Update-Note: If a x86 Windows asm build breaks, switch from Yasm to
NASM. We're also no longer testing NASM on x86_64 Windows, but there
wasn't any patch to revert.
Change-Id: I016bad8757fcc13240db9f56dd622be518e649d7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44564
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>