Add python bindings for IREE internal dialects. (#14770)

I've been running into these recently when wanting to create helper
scripts. Also some of these will be helpful for Turbine.
diff --git a/compiler/bindings/python/test/ir/dialects_test.py b/compiler/bindings/python/test/ir/dialects_test.py
new file mode 100644
index 0000000..63a9603
--- /dev/null
+++ b/compiler/bindings/python/test/ir/dialects_test.py
@@ -0,0 +1,16 @@
+# Copyright 2023 The IREE Authors
+#
+# Licensed under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+from iree.compiler import ir
+
+# Make sure that our dialects import.
+from iree.compiler.dialects import (
+    flow,
+    hal,
+    stream,
+    vm,
+    util,
+)