Input: ims-pcu - validate control endpoint type

Input: ims-pcu - validate control endpoint type

The driver currently assumes that the first endpoint of the control
interface is an interrupt IN endpoint without verifying it. A malicious
device could provide a different endpoint type, which would then be
passed to usb_fill_int_urb(), potentially leading to kernel warnings
or undefined behavior.

Verify that the control endpoint is an interrupt IN endpoint.

Fixes: 628329d52474 ("Input: add IMS Passenger Control Unit driver")
Cc: stable@vger.kernel.org
Reported-by: Sashiko bot <sashiko-bot@kernel.org>
Assisted-by: Gemini:gemini-3.1-pro
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>