usb: phy: fsl-usb: add IRQ check

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

Fixes: 0807c500 ("USB: add Freescale USB OTG Transceiver driver")
Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/b0a86089-8b8b-122e-fd6d-73e8c2304964@omp.ruSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/phy/phy-fsl-usb.c

@@ -873,6 +873,8 @@ int usb_otg_start(struct platform_device *pdev)
 
 	/* request irq */
 	p_otg->irq = platform_get_irq(pdev, 0);
+	if (p_otg->irq < 0)
+		return p_otg->irq;
 	status = request_irq(p_otg->irq, fsl_otg_isr,
 				IRQF_SHARED, driver_name, p_otg);
 	if (status) {