Auto merge of #76326 - mati865:use_lld-no-linker, r=Mark-Simulacrum
Auto merge of #76326 - mati865:use_lld-no-linker, r=Mark-Simulacrum

Fix rust.use-lld when linker is not set

Fixes https://github.com/rust-lang/rust/pull/76127#issuecomment-685419195

Previously when `[<target>].linker` was not configured `rust.use-lld` would set it to `rust-lld` on platforms where it should not.

aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust