[mlir][memref] Make `finalize-memref-to-llvm` the last MemRef passusers/matthias-springer/finalize_memref

This commit updates all test cases and pass pipelines such that `finalize-memref-to-llvm` is the last pass that deals with MemRef types. (As the name already suggests.) This is now also mentioned in the pass documentation.

This change is preparation of merging the 1:1 and 1:N dialect conversions. As part of that change, argument materializations are going to disappear.

To understand why `finalize-memref-to-llvm` should be the final MemRef pass, consider this example:
```mlir
// RUN: mlir-opt -convert-func-to-llvm
func.func @foo(%m: memref<5xf32>) {
  %r = vector.transfer_read %m[...] ...
 ...
}
```

The output (assuming bare pointer calling convention) will be as follows:
```mlir
func.func @foo(%ptr: !llvm.ptr) {
  %m = builtin.unrealized_conversion_cast %ptr : !llvm.ptr to memref<5xf32>
}
```

1 files changed, 1 insertions, 1 deletions

diff --git a/mlir/unittests/ExecutionEngine/Invoke.cpp b/mlir/unittests/ExecutionEngine/Invoke.cpp
index ff87fc9..b945396 100644
--- a/mlir/unittests/ExecutionEngine/Invoke.cpp
+++ b/mlir/unittests/ExecutionEngine/Invoke.cpp
@@ -53,9 +53,9 @@ static struct LLVMInitializer {
 /// dialects lowering to LLVM Dialect.
 static LogicalResult lowerToLLVMDialect(ModuleOp module) {
   PassManager pm(module->getName());
-  pm.addPass(mlir::createFinalizeMemRefToLLVMConversionPass());
   pm.addNestedPass<func::FuncOp>(mlir::createArithToLLVMConversionPass());
   pm.addPass(mlir::createConvertFuncToLLVMPass());
+  pm.addPass(mlir::createFinalizeMemRefToLLVMConversionPass());
   pm.addPass(mlir::createReconcileUnrealizedCastsPass());
   return pm.run(module);
 }