[keymap] Fix PS3 dualshock for SDL2

Keymap for PS3 needed some work. The layout now resembles the 360 keymap as found on the [wiki](http://kodi.wiki/view/Xbox_360_Wireless_Controller_for_Windows) Also, with SDL2 all the controller buttons are mapped to axes so that they are "touch sensitive", and we need to tell kodi which axes correspond to these buttons.