ohci: fix Host Controller USBRESET

ohci: fix Host Controller USBRESET

Specification says that, when entering this state, "the contents of the registers
(except Root Hub registers) are preserved by the HC. [...] The Root Hub is being reset,
which causes the Root Hub's downstream ports to be reset and possibly powered off."

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-id: 1450567431-31795-3-git-send-email-hpoussin@reactos.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>