More sensible USB support for H10: plugging in puts it into USB charging mode and leaves Rockbox usable, holding 'O' while pluggin in the USB cable will reboot the H10 (continuing to hold 'O' starts it up in UMS mode), holding any other button brings up the USB screen as previously.
Implement system_reboot() for all PP5020 devices.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@11015 a1c6a512-1295-4272-9138-f99709370657