Rollup merge of #49045 - Zoxc:tls, r=michaelwoerister

Make queries thread safe

This makes queries thread safe by removing the query stack and making queries point to their parents. Queries write to the query map when starting and cycles are detected by checking if there's already an entry in the query map. This makes cycle detection O(1) instead of O(n), where `n` is the size of the query stack.

This is mostly corresponds to the method I described [here](https://internals.rust-lang.org/t/parallelizing-rustc-using-rayon/6606).

cc @rust-lang/compiler

r? @michaelwoerister

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