Auto merge of #80087 - davidtwco:issue-80086-llvm-dwp-in-ci-llvm, r=Mark-Simulacrum
Auto merge of #80087 - davidtwco:issue-80086-llvm-dwp-in-ci-llvm, r=Mark-Simulacrum

bootstrap: include llvm-dwp in CI LLVM

Fixes #80086.

This PR includes the `llvm-dwp` tool in the CI LLVM (which rustc developers can download instead of building LLVM locally) - `llvm-dwp` is required by Split DWARF which landed in PR #77117.

r? `@Mark-Simulacrum`

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