usb: ehci-pci: Set PROBE_PREFER_ASYNCHRONOUS

This driver often takes on the order of 8ms to start, but every little
bit counts. It shouldn't have many cross-device dependencies to
race with, nor racy access to shared state with other drivers, so this
should be a relatively low risk change.

This driver was pinpointed as part of a survey of top slowest initcalls
(i.e., are built in, and probing synchronously) on a lab of ChromeOS
systems.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20221028184507.v2.1.I9a5353f81d1509f85f3a04f0cdc9099f6fe60811@changeidSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-pci.c

@@ -411,11 +411,12 @@ static struct pci_driver ehci_pci_driver = {
 	.remove =	ehci_pci_remove,
 	.shutdown = 	usb_hcd_pci_shutdown,
 
-#ifdef CONFIG_PM
 	.driver =	{
-		.pm =	&usb_hcd_pci_pm_ops
-	},
+#ifdef CONFIG_PM
+		.pm =	&usb_hcd_pci_pm_ops,
 #endif
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
 };
 
 static int __init ehci_pci_init(void)