Auto merge of rust-lang#34055 - brson:cmake, r=alexcrichton

Convert makefiles to build LLVM/compiler-rt with CMake

This is certainly buggy, but I have successfully built on x86_64-unknown-linux-gnu and x86_64-pc-windows-gnu. I haven't built successfully on mac yet, and I've seen mysterious test failures on Linux, but I'm interested in throwing this at the bots to see what they think.

1.9.0 release

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1.1.0 release