[mlir] support dialect attribute translation to LLVM IR (#75309)

Extend the `amendOperation` mechanism for translating dialect attributes
attached to operations from another dialect when translating MLIR to
LLVM IR. Previously, this mechanism would have no knowledge of the LLVM
IR instructions created for the given operation, making it impossible
for it to perform local modifications such as attaching operation-level
metadata. Collect instructions inserted by the LLVM IR builder and pass
them to `amendOperation`.