Remove _StridedLayout from cuda.core public API

_StridedLayout is a private symbol (underscore-prefixed) that was
imported from cuda.core._layout into cuda/core/__init__.py, making it
unintentionally available as a public name. All internal usage
(in _memoryview.pyx) already imports it directly via cimport from the
private module, so the re-export in __init__.py is unnecessary.

Author: mdboom

cuda_core/cuda/core/__init__.py

@@ -34,7 +34,6 @@
 from cuda.core._graphics import GraphicsResource
 from cuda.core._launch_config import LaunchConfig
 from cuda.core._launcher import launch
-from cuda.core._layout import _StridedLayout
 from cuda.core._linker import Linker, LinkerOptions
 from cuda.core._memory import (
     Buffer,