Fix a bunch of warnings

Mostly adding __unused where needed.

Change-Id: Ia4f675b9b360782728c361ed1699db0cc277c3a5
diff --git a/gui/object.cpp b/gui/object.cpp
index eae56e6..206f2c7 100644
--- a/gui/object.cpp
+++ b/gui/object.cpp
@@ -141,7 +141,7 @@
 	return !mConditions.empty();
 }
 
-int GUIObject::NotifyVarChange(const std::string& varName, const std::string& value)
+int GUIObject::NotifyVarChange(const std::string& varName, const std::string& value __unused)
 {
 	mConditionsResult = UpdateConditions(mConditions, varName);
 	return 0;