use LLD linker for Darwin

[garymm]

LLD supports Darwin / Mach-O now: https://lld.llvm.org/MachO/index.html

And it's supposedly ~2-3x faster.

Just filing for reference since I saw this and noticed it was false:
https://github.com/grailbio/bazel-toolchain/blob/0f210543780f15e08436b3b6975ac2e11fead00b/toolchain/internal/configure.bzl#L169

[garymm]

CC @dzbarsky since your recent PR is what got me looking at this.

[keith]

Note that as of Xcode 15 (released next week) performance isn't as much of a win.

[garymm]

Well still seems better for the toolchain to have as few non-hermetic deps as possible

[DavidZbarsky-at]

+1 to using LLD and avoiding the host dependency. I tried it out but saw issues with clang not recognizing the fuse-ld flag. I'm sure I was holding it wrong somehow, if anyone has a few cycles to play with it, would be a nice win.

[siddharthab]

Sent #286 as an attempt. It needs more work for rules_go and rules_foreign_cc, but otherwise seems to be working. Any help here is appreciated. I may not be able to get it to it anytime soon.

[siddharthab]

#286 adds support for this but does not make it default. Users are requested to test on their projects and report. If it seems to be working, we can make it the default.