Auto merge of #106429 - djkoloski:add_vendor_to_fuchsia_target_triple, r=nagisa

Add vendor to Fuchsia's target triple

Historically, Rust's Fuchsia targets have been labeled x86_64-fuchsia and aarch64-fuchsia. However, they should technically contain vendor information. This CL changes Fuchsia's target triples to include the "unknown" vendor since Clang now does normalization and handles all triple spellings.

This was previously attempted in #90510, which was closed due to inactivity.

diff --cc compiler/rustc_target/src/spec/mod.rs
Simple merge