Rollup merge of #63558 - jgalenson:move-remap, r=alexcrichton
Rollup merge of #63558 - jgalenson:move-remap, r=alexcrichton

Remap paths for proc-macro crates.

The remap-debuginfo config option remaps paths in most crates, but it does not apply to proc-macros, so they are still non-reproducible.  This patch fixes that.

I'm not completely sure if this is the best way to do this, but to get reproducible builds we need librustc_macros to be built with --remap-path-prefix.  I was previously modifying Cargo to pass that argument to all child crates, so this seems simpler and more correct.

I did not add a test since there do not seem to be any existing tests for RUSTC_DEBUGINFO_MAP.

r? @alexcrichton

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