Fixing build errors

Signed-off-by: Abhishek Malik <abhishek.malik@intel.com>

src/button/javaupm_button.i

@@ -1,6 +1,8 @@
 %module javaupm_button
 %include "../upm.i"
 
+%apply int {mraa::Edge}
+
 %{
     #include "button.hpp"
 %}