MidiControlListener: replaced static numActions by enum constant

It's not a good idea to have a separate constant determining the number
of items in an enumeration because you can easily get inconsistencies.
Use the last element of enumeration as NumActions constant instead.

Signed-off-by: Tobias Doerffel <tobias.doerffel@gmail.com>

include/midi_control_listener.h

@@ -47,9 +47,9 @@ public:
 		ActionStop,
 		ActionToggleLoop,
 		ActionJumpToLoopStart,
-		ActionJumpToLoopEnd
+		ActionJumpToLoopEnd,
+		NumActions
 	} EventAction;
-	static const int numActions = 7;
 	
 	typedef QMap<int, EventAction> ActionMap;