[llvm-ir2vec] Creating one directory per library for IRUtils, and MIRUtils (#198170) Follow up to https://github.com/llvm/llvm-project/pull/194414#issuecomment-4467455664 . Made a patch to move IRUtils, and MIRUtils to their own subdirectories GitOrigin-RevId: b9c7a8e43ac26b0df422cd9a403382f0656785a0