usb: gadget: udc: at91: add IRQ check

usb: gadget: udc: at91: add IRQ check

The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_irq() (which takes
*unsigned* IRQ #), causing it to fail with -EINVAL, overriding an original
error code. Stop calling devm_request_irq() with the invalid IRQ #s.

Fixes: 8b2e76687b39 ("USB: AT91 UDC updates, mostly power management")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Acked-by: Felipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/6654a224-739a-1a80-12f0-76d920f87b6c@omp.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>