make module reloadable on iMx6
Detail: The iMx6 root hubs have an annoying quirk in that if a device is disconnected from the root port an interrupt is missing on subsequent reconnects at high speed. This mod resets the whole root hub when it detects a disconnect so it gets a 'first time' connect each time.
Additionally the chip is left in port reset state when the module dies. This facilitates reload of the module.
These mods are tested on the iMx6 platform.