HID: cp2112: Fix driver not registering GPIO IRQ chip as threaded

The CP2112 generates interrupts from a polling routine on a thread,
and can only support threaded interrupts. This patch configures the
gpiochip irq chip with this flag, disallowing consumers to request
a hard IRQ from this driver, which resulted in a segfault previously.

Signed-off-by: Danny Kaehn <kaehndan@gmail.com>
Link: https://lore.kernel.org/r/20230210170044.11835-1-kaehndan@gmail.com
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>