Update policy handling for USB inputs

Adapted from:
https://github.com/CyanogenMod/android_hardware_libhardware_legacy/commit/fd61179b6483f1c6360968d0f9f7695ea6f380a7

This quite bad adaptation but I guess we would need to update
our HAL a lot more to catch up on everything.

TODO later I suppose. At least it compiles now.

Change-Id: Ic19363e09bf2ce6dd3c77b28698e8b4c8fadf67f