Deprecate Windows OS support

Unfortunately the Winstackers project has been retired because of no
maintainers[1][2], and OpenStack on Windows host is no longer
maintained.

[1] https://lists.openstack.org/pipermail/openstack-discuss/2022-November/031044.html
[2] https://review.opendev.org/c/openstack/governance/+/886880

Change-Id: I97a441700304765e6db33f3827d5146fed09a919

os_brick/initiator/windows/base.py

@@ -13,6 +13,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import warnings
+
 from os_win import utilsfactory
 from oslo_concurrency import processutils as putils
 from oslo_log import log as logging
@@ -33,6 +35,8 @@ class BaseWindowsConnector(initiator_connector.InitiatorConnector):
     DEFAULT_DEVICE_SCAN_INTERVAL = 2
 
     def __init__(self, root_helper=None, *args, **kwargs):
+        warnings.warn('Support for Windows OS has been deprecated.',
+                      category=DeprecationWarning, stacklevel=2)
         kwargs['executor'] = kwargs.get('executor') or putils.execute
         super(BaseWindowsConnector, self).__init__(root_helper,
                                                    *args, **kwargs)

os_brick/remotefs/windows_remotefs.py

@@ -17,6 +17,7 @@
 
 import os
 import re
+import warnings
 
 from os_win import utilsfactory
 from oslo_log import log as logging
@@ -35,6 +36,8 @@ class WindowsRemoteFsClient(remotefs.RemoteFsClient):
 
     def __init__(self, mount_type, root_helper=None,
                  execute=None, *args, **kwargs):
+        warnings.warn('Support for Windows OS has been deprecated.',
+                      category=DeprecationWarning, stacklevel=2)
         mount_type_to_option_prefix = {
             'cifs': 'smbfs',
             'smbfs': 'smbfs',

releasenotes/notes/deprecate-windows-support-bdc643525e9bb132.yaml

@@ -0,0 +1,5 @@
+---
+deprecations:
+  - |
+    Support for Windows operating systems has been deprecated, because of
+    retirement of the Winstackers project.