usb: cdns3: delete role_override

usb: cdns3: delete role_override

In short, we have three kinds of role switches:
- Based on SoC: ID and VBUS
- Based on external connnctor, eg, Type-C or GPIO Connector
- Based on user choices through sysfs

Since HW handling and usb-role-switch handling are at
different places, we do not need role_override any more,
and this flag could not judge external connector case well.

With role_override deleted, We use cdns3_hw_role_switch for
the 1st use case, and usb-role-switch for the 2nd and 3rd cases.

Reviewed-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>