The mailbox register for usb otg in omap is present in control module.
On detection of any events VBUS or ID, this register should be written
to send the notification to musb core.

Till we have a separate control module driver to write to control module,
omap2430 will handle the register writes to control module by itself. So
a new address space to represent this control module register is added
to usb_otg_hs.
Acked-by: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>