USB: Handle auto-transition from hot to warm reset.

USB 3.0 hubs and roothubs will automatically transition a failed
hot
reset to a warm (BH) reset.  In that case, the warm reset change
bit
will be set, and the link state change bit may also be set.
Change
hub_port_finish_reset to unconditionally clear those change bits
for USB
3.0 hubs.  If these bits are not cleared, we may lose port
change events
from the roothub.

This commit should be backported to
kernels as old as 3.2, that contain
the commit 75d7cf7 "usbcore:
refine
warm reset logic".

Signed-off-by: Sarah Sharp
<sarah.a.sharp@linux.intel.com>
Acked-by: Alan Stern
<stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman
<gregkh@linuxfoundation.org>

idea is taken here -
https://github.com/varunchitre15/thunderzap_xl/commit/d1c2ab8e957a502cd41e30c041bf730318229eb9