HID: holtek: Holtek devices depends on USB_HID

In the HID drivers tranport cleanup series, I removed the dependency
between hid-holtek and usbhid. This was wrong as hid-holtek.c relies
extensively on usb calls.

This fixes compilation error when CONFIG_USB_SUPPORT is not enabled.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>