Add the google-global-names-in-headers rule to the list of clang-tidy checks to prevent namespace pollution.
This is intended to flag global using-directives in header files during PR checks. Collisions between the llvm and the mlir namespace have caused obscure build failures on Windows in the past. #6844 should have removed all existing occurrences in the CIRCT code base.
MLIR's clang-tidy configuration inherits from LLVM's,
so this was updated to the merged configuration.
Using `--list-checks` to compare the final set of checks
and `--dump-config` to compare their configuration
(but not Checks, since there's duplication due to inheritance)
Config:
* Dropped naming exception for 'LLVMFuzzerTestOneInput'
Checks:
* We still have misc-no-recursion, upstream dropped.
And are otherwise the same.
fzi-hielscher