PM: Do not acquire device semaphores upfront during suspend

Remove the code that acquires all device semaphores from the suspend
code path as it causes multiple problems to appear (most notably,
http://bugzilla.kernel.org/show_bug.cgi?id=10030) and revert the
change introduced by commit 4145ed6dc597a9bea5f6ae8c574653b2de10620f
depending on the code being removed.

Remove pm_sleep_lock()/pm_sleep_unlock() from device_add() to avoid
the issue reported at http://bugzilla.kernel.org/show_bug.cgi?id=9874.

It should fix the regreesions reported at:
	http://bugzilla.kernel.org/show_bug.cgi?id=9874
	http://bugzilla.kernel.org/show_bug.cgi?id=10030

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index f6f1990..1f0db51 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -233,7 +233,7 @@
 	 * singlethreaded.  Its job doesn't justify running on more
 	 * than one CPU.
 	 */
-	ksuspend_usb_wq = create_singlethread_workqueue("ksuspend_usbd");
+	ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd");
 	if (!ksuspend_usb_wq)
 		return -ENOMEM;
 	return 0;