[MLIR] Fix circular dependency introduced in In https://github.com/llvm/llvm-project/pull/144897. This PR is to break the dependency. by moving StateStack to IR folder This commit resolves a circular dependency issue between mlir/Support and mlir/IR: - Move StateStack.h and StateStack.cpp from Support to IR folder - Update CMakeLists.txt files to reflect the new locations - Update Bazel BUILD file to maintain correct dependencies - Update includes in affected files (flang, Target/LLVMIR) The circular dependency was caused by StateStack.h depending on IR/Visitors.h while other IR files depended on Support. Moving StateStack to IR eliminates this cycle while maintaining proper separation of concerns.
Multi-Level Intermediate Representation
See https://mlir.llvm.org/ for more information.