Add CMAKE_ARGS option in mlir

[vincentmr]

Context: It is necessary to pass custom CMake options such as -DCMAKE_CXX_FLAGS='-stdlib=libc++' to the MLIR config to build MLIR with clang-19. One convenient way to deal with that is have CMAKE_ARGS as in the runtime.

Description of the Change: Add optional CMAKE_ARGS to pass arbitrary CMake options to the MLIR build.

Benefits:

Possible Drawbacks:

Related GitHub Issues:

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