USB: ohci-exynos: replace hcd->state with ohci->rh_state

This patch removes uses of hcd->state and replaces hcd->state with
ohci->rh_state field.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>