[mlir][LLVM] Remove `llvm` deps from the LLVM dialect (#150692)

This patch removes spurious includes of `llvm/IR` files, and unnecessary
link components in the LLVM dialect.

The only major dependencies still coming from LLVM are
`llvm::DataLayout`, which is used by `verifyDataLayoutString` and some
`dwarf` symbols in some attributes. Both of them should likely be
removed in the future.

Finally, I also removed one constructor from `LLVM::AssumeOp` that used
[OperandBundleDefT](https://llvm.org/doxygen/classllvm_1_1OperandBundleDefT.html)
without good reason and introduced a header unnecessarily.

0 files changed, 0 insertions, 0 deletions