rockchip: rock-pi-4: Enable USB3 Host

rockchip: rock-pi-4: Enable USB3 Host

Enable USB3.0 Host support for RockPI-4 boards.

Note that the Upper USB3.0 port is marked as otg and
lower USB3.0 port marked as host, so this below log
capture when USB3.0 mass storage plug in at lower
USB 3.0 port.

Log:
Bus usb@fe380000: USB EHCI 1.00
Bus usb@fe3c0000: USB EHCI 1.00
Bus dwc3: usb maximum-speed not found
Register 2000140 NbrPorts 2
Starting the controller
USB XHCI 1.10
Bus dwc3: usb maximum-speed not found
Register 2000140 NbrPorts 2
Starting the controller
USB XHCI 1.10
scanning bus usb@fe380000 for devices... 1 USB Device(s) found
scanning bus usb@fe3c0000 for devices... 1 USB Device(s) found
scanning bus dwc3 for devices... 1 USB Device(s) found
scanning bus dwc3 for devices... cannot reset port 1!?
2 USB Device(s) found
       scanning usb for storage devices... 1 Storage Device(s) found
=> usb tree
USB device tree:
  1  Hub (480 Mb/s, 0mA)
     u-boot EHCI Host Controller

  1  Hub (480 Mb/s, 0mA)
     u-boot EHCI Host Controller

  1  Hub (5 Gb/s, 0mA)
     U-Boot XHCI Host Controller

  1  Hub (5 Gb/s, 0mA)
  |  U-Boot XHCI Host Controller
  |
  +-2  Mass Storage (5 Gb/s, 224mA)
       SanDisk Dual Drive 040130e3ee554b7078843f4eb331646

Cc: Tom Cubie <tom@radxa.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>