fence_lpar: Add "Error" in the list of on states

When the LPAR crashes it can stay in Error state.

It's no possible to transition to 'Running' state from 'Error' but it's
possible to power off the LPAR. Then for all parctical purposes 'Error'
is an on state.

Fixes: ClusterLabs#610

agents/lpar/fence_lpar.py

@@ -20,7 +20,7 @@
 ##
 ## Transformation to standard ON/OFF status if possible
 def _normalize_status(status):
-	if status in ["Running", "Open Firmware", "Shutting Down", "Starting"]:
+	if status in ["Running", "Open Firmware", "Shutting Down", "Starting", "Error"]:
 		status = "on"
 	else:
 		status = "off"