HID: lenovo: Rework how the tp10ubkbd code decides which USB interface to use

Instead of looking for a hdev with a type of HID_TYPE_USBMOUSE find
the interface for the mute/mic-mute/fn-lock LEDs by checking for the
output-report which is used to set them.

This is a preparation patch for adding support for the LEDs on the
X1 tablet thin keyboard which uses the same output-report, but has
a separate (third) USB interface for the touchpad/mouse functionality.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>