Revert "usb-hub: report status changes only once"

Revert "usb-hub: report status changes only once"

This reverts commit a309ee6e0a256f690760abfba44fceaa52a7c2f3.

This isn't in line with the usb specification and adds regressions,
win7 fails to drive the usb hub for example.

Was added because it "solved" the issue of hubs interacting badly
with the xhci host controller.  Now with the root cause being fixed
in xhci (commit <FIXME>) we can revert this one.

Cc: qemu-stable@nongnu.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit bdebd6ee81f4d849aa8541c289203e3992450db0)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>