USB: host: ohci-at91: completely shutdown the controller in at91_stop_hc()

USB: host: ohci-at91: completely shutdown the controller in at91_stop_hc()

When removing the ohci-at91 module, the fact of not running complete shutdown
of all the ports was keeping additional analog cells consuming power for no
reason.
Doing Reset (OHCI_HCR) to HcCommandStatus register is the way to go, but using
the OHCI controller shutdown procedure is just perfect for this.

Signed-off-by: Boris Krasnovskiy <Boris.Krasnovskiy@lairdconnect.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20190911064154.28633-2-nicolas.ferre@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>