USB: EHCI: ehci-mv: fix less than zero comparison of an unsigned int

The comparison of hcd->irq to less than zero for an error check will
never be true because hcd->irq is an unsigned int.  Fix this by
assigning the int retval to the return of platform_get_irq and checking
this for the -ve error condition and assigning hcd->irq to retval.

Addresses-Coverity: ("Unsigned compared against 0")
Fixes: c856b4b0 ("USB: EHCI: ehci-mv: fix error handling in mv_ehci_probe()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200515165453.104028-1-colin.king@canonical.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-mv.c

@@ -166,11 +166,10 @@ static int mv_ehci_probe(struct platform_device *pdev)
 	hcd->rsrc_len = resource_size(r);
 	hcd->regs = ehci_mv->op_regs;
 
-	hcd->irq = platform_get_irq(pdev, 0);
-	if (hcd->irq < 0) {
-		retval = hcd->irq;
+	retval = platform_get_irq(pdev, 0);
+	if (retval < 0)
 		goto err_disable_clk;
-	}
+	hcd->irq = retval;
 
 	ehci = hcd_to_ehci(hcd);
 	ehci->caps = (struct ehci_caps __iomem *) ehci_mv->cap_regs;