xhci: Add usb cold attach (CAS) as a reason to resume root hub.

Check for the cold attach (CAS) bit while checking for other usb3
roothub port changes during host resume.

The CAS bit is set if a USB 3 device is connected while the host is
suspended in such a way it can't perform proper link training and
progress the link to the enabled U0 state.

If the CAS bit set we want to resume the root hub, and reset and
enumerate the newly connected device.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Message-ID: <20230602144009.1225632-3-mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci.c

@@ -833,7 +833,7 @@ static bool xhci_pending_portevent(struct xhci_hcd *xhci)
 	ports = xhci->usb3_rhub.ports;
 	while (port_index--) {
 		portsc = readl(ports[port_index]->addr);
-		if (portsc & PORT_CHANGE_MASK ||
+		if (portsc & (PORT_CHANGE_MASK | PORT_CAS) ||
 		    (portsc & PORT_PLS_MASK) == XDEV_RESUME)
 			return true;
 	}