CORD-898: Limit list of categories until we see the need to add more

Change-Id: I24a7e4f7e2956164012cbfa646e554bc38b94661
diff --git a/voltha/core/adapter_agent.py b/voltha/core/adapter_agent.py
index edcf236..e7a26f8 100644
--- a/voltha/core/adapter_agent.py
+++ b/voltha/core/adapter_agent.py
@@ -326,7 +326,7 @@
     def create_alarm(self, id=None, resource_id=None, description=None,
                      raised_ts=0, changed_ts=0,
                      type=AlarmEventType.EQUIPMENT,
-                     category=AlarmEventCategory.GENERAL,
+                     category=AlarmEventCategory.PON,
                      severity=AlarmEventSeverity.MINOR,
                      state=AlarmEventState.RAISED,
                      context=None):
diff --git a/voltha/protos/events.proto b/voltha/protos/events.proto
index 6203c3f..8fe434c 100644
--- a/voltha/protos/events.proto
+++ b/voltha/protos/events.proto
@@ -71,10 +71,7 @@
  */
 message AlarmEventCategory {
     enum AlarmEventCategory {
-        GENERAL = 0;
-        CONFIGURATION = 1;
-        PON = 2;
-        TCA = 3;
+        PON = 0;
     }
 }
 
@@ -109,19 +106,15 @@
     string id = 1;
 
     // Refers to the area of the system impacted by the alarm
-    // COMMUNICATION, ENVIRONMENT, EQUIPMENT, SERVICE, PROCESSING, SECURITY
     AlarmEventType.AlarmEventType type = 2;
 
-    // Refers to the functional category originating the alarm
-    // GENERAL, CONFIG, PON, TCA
+    // Refers to functional category of the alarm
     AlarmEventCategory.AlarmEventCategory category = 3;
 
     // Current active state of the alarm
-    // RAISED, CLEARED
     AlarmEventState.AlarmEventState state = 4;
 
     // Overall impact of the alarm on the system
-    // INDETERMINATE, WARNING, MINOR, MAJOR, CRITICAL
     AlarmEventSeverity.AlarmEventSeverity severity = 5;
 
     // Timestamp at which the alarm was first raised