Allow sysdataset move if AD faulted (#11600)

This has knock-on effects regarding failover when AD is broken.
We should ensure that it's always possible to get system dataset
set up, and in principle if AD join is already broken things
can't really get worse by moving around the system dataset.

(cherry picked from commit 980a4de5a6d36663dd30b4f8504bb44d13f7c16a)
Co-authored-by: Andrew Walker <awalker@ixsystems.com>

src/middlewared/middlewared/plugins/sysdataset.py

@@ -103,7 +103,7 @@ class SystemDatasetService(ConfigService):
         verrors = ValidationErrors()
         if new['pool'] != config['pool']:
             system_ready = await self.middleware.call('system.ready')
-            ad_enabled = (await self.middleware.call('activedirectory.get_state')) in ['HEALTHY', 'FAULTED']
+            ad_enabled = (await self.middleware.call('activedirectory.get_state')) == 'HEALTHY'
             if system_ready and ad_enabled:
                 verrors.add(
                     'sysdataset_update.pool',