During usb_hub_port_connect_change(), a port reset set feature
request is issued to the port, and later a port reset clear feature
is done to the same port before the function returns. However at
the end of usb_scan_port(), we attempt to clear port reset again
on a cached port status change variable, which should not be done.

Adjust the call to clear port reset to right before the call to
usb_hub_port_connect_change().

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>