7682f663b5
LLVM IR currently [accepts](https://godbolt.org/z/nqnEsW1ja): ``` define void @incompatible_call_and_callee_types() { call void @callee(i64 0) ret void } define void @callee({ptr, i64}, i32) { ret void } ``` This currently fails to import. Even though these constructs are dangerous and probably indicate some ODR violation (or optimization bug), they are "valid" and should be imported into LLVM IR dialect. This PR implements that by using an indirect call to represent it. Translation already works nicely and outputs the same source llvm IR file. The error is now a warning, the tests in `mlir/test/Target/LLVMIR/Import/import-failure.ll` already use `CHECK` lines, so no need to add extra diagnostic tests.
Multi-Level Intermediate Representation
See https://mlir.llvm.org/ for more information.