Rollup merge of #82256 - eddyb:time-passes-stderr, r=varkor

Print -Ztime-passes (and misc stats/logs) on stderr, not stdout.

I've tried not to change anything that looked similar to `rustc --print`, where people might use automation, and/or any "bulk" prints, such as dumping an entire Graphviz (`dot`) graph on stdout.

The reason I want `-Ztime-passes` to be on stderr like debug logging is I can get a complete (and correctly interleaved) view just by looking at stderr, which is merely a convenience when running `rustc`/Cargo directly, but even more important when it's nested in a build script, as Cargo will split the build script output into stdout (named `output`) and `stderr`.