USB: EHCI: fix compiler warning introduced by commit 2a40f324

Fix the following compiler warning (found by the kbuild test robot):

drivers/usb/host/ehci-hcd.c:312:13: warning: 'unlink_empty_async_suspended' declared 'static' but never defined

Commit 2a40f324 ("USB: EHCI: fix regression during bus resume")
protected the function definition with a "#ifdef CONFIG_PM" block, so
now the declaration needs to be similarly protected.  This patch moves
it to a better location.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-hcd.c

@@ -309,7 +309,6 @@ static void ehci_quiesce (struct ehci_hcd *ehci)
 static void end_iaa_cycle(struct ehci_hcd *ehci);
 static void end_unlink_async(struct ehci_hcd *ehci);
 static void unlink_empty_async(struct ehci_hcd *ehci);
-static void unlink_empty_async_suspended(struct ehci_hcd *ehci);
 static void ehci_work(struct ehci_hcd *ehci);
 static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh);
 static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh);

drivers/usb/host/ehci-hub.c

@@ -33,6 +33,8 @@
 
 #ifdef	CONFIG_PM
 
+static void unlink_empty_async_suspended(struct ehci_hcd *ehci);
+
 static int persist_enabled_on_companion(struct usb_device *udev, void *unused)
 {
 	return !udev->maxchild && udev->persist_enabled &&