JackRequest: Add missing comma

allowed by compiler and helps with clean commit history when
adding changes

Change-Id: Iaafbe0a01970cf1b176a24d8fdc8cc6ee5c97e3b
Signed-off-by: Adam Miartus <amiartus@de.adit-jv.com>

common/JackRequest.h

@@ -90,7 +90,7 @@ struct JackRequest
         kGetUUIDByClient = 37,
         kClientHasSessionCallback = 38,
         kComputeTotalLatencies = 39,
-        kPropertyChangeNotify = 40
+        kPropertyChangeNotify = 40,
     };
 
     RequestType fType;