fix: expand variables in Plugin._verify_all_device_commands

Need to expand variables before calling the @command function. This is
actually done for _execute_all[_non]_device_commands and
_verify_all_non_device_commands, but not in _verify_all_device_commands.
This adds the missing expansion.

Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>

tuned/plugins/base.py

@@ -460,7 +460,7 @@ def _verify_all_non_device_commands(self, instance, ignore_missing):
 	def _verify_all_device_commands(self, instance, devices, ignore_missing):
 		ret = True
 		for command in [command for command in list(self._commands.values()) if command["per_device"]]:
-			new_value = instance.options.get(command["name"], None)
+			new_value = self._variables.expand(instance.options.get(command["name"], None))
 			if new_value is None:
 				continue
 			for device in devices: