FIX: do not popup OSD on DVD menu with touch or mouse (fixes #14906)

/cc @jmarshallnz @Memphiz 
ref: http://forum.xbmc.org/showthread.php?tid=180952

This prevents the osd to pop up on a tap or mouse move when a dvd menu is displayed.

pro:
- Prevents the dvd menu to be overlapped by the osd
- Leaner

con:
- No way to stop the dvd with touch or mouse when on a menu. You have to leave fullscreen.