This patch splits the ohci-platform code from ohci-hcd out
into its own separate driver module.This work is part of enabling
multi-platform kernels on ARM.
In V2:
-Passed "hcd" argument instead of "ohci" in ohci_setup() because it is
using "struct usb_hcd" argument.
In V3:
-Directly passed "hcd" argument not required to call ohci_to_hcd() function.