[mlir][core] Add an MLIR "pattern catalog" generator (#146228)

This PR adds a feature that attaches a listener to all RewritePatterns that
logs information about the modified operations.

When the MLIR test suite is run, these debug outputs can
be filtered and combined into an index linking operations to the
patterns that insert, modify, or replace them. This index is intended to
be used to create a website that allows one to look up patterns from an
operation name.

The debug logs emitted can be viewed with --debug-only=generate-pattern-catalog, 
and the lit config is modified to do this when the env var MLIR_GENERATE_PATTERN_CATALOG is set.

Example usage:

```
mkdir build && cd build
cmake -G Ninja ../llvm \
  -DLLVM_ENABLE_PROJECTS="mlir" \
  -DLLVM_TARGETS_TO_BUILD="host" \
  -DCMAKE_BUILD_TYPE=DEBUG
ninja -j 24 check-mlir
MLIR_GENERATE_PATTERN_CATALOG=1 bin/llvm-lit -j 24 -v -a tools/mlir/test | grep 'pattern-logging-listener' | sed 's/^# | [pattern-logging-listener] //g' | sort | uniq > pattern_catalog.txt
```

Sample pattern catalog output (that fits in a gist):
https://gist.github.com/j2kun/02d1ab8d31c10d71027724984c89905a

---------

Co-authored-by: Jeremy Kun <j2kun@users.noreply.github.com>
Co-authored-by: Mehdi Amini <joker.eph@gmail.com>

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