usb: chipidea: add controller reset API

Add controller reset API, currently it is used for device mode only.
It may be used for host/otg driver in future.

Ususally, we need this API for dual-role switch and back from hibernation
suspend to let the controller at default state.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
usb: chipidea: parameter 'mode' isn't needed for hw_device_reset

The hw_device_reset is dedicated to be used at device mode initializaiton,
so delete the parameter 'mode'. For host driver, the ehci driver will
handle all things.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
usb: chipidea: remove duplicate dev_set_drvdata for host_start

The core driver has already done it, besides, move set driver data
operation just after ci has allocated successfully in case some
code (like ci_role_start) want to access this driver data.

Signed-off-by: Peter Chen <peter.chen@freescale.com>