persimmon: complete the sb800 devicetree

persimmon: complete the sb800 devicetree

sb800 cimx entry sb_Before_Pci_Init was called in the device 16.2
enable_dev() function. If the devicetree don't have this device,
then sb_Before_Pci_Init will not get called.
So the missing sb800 USB3 devicees was add to the mainboard devicetree.
Because of no physical usb connector connected to USB3, the USB3 device setting was off.

Change-Id: If060ccb43df7fbe88bafc61e9e600a9120575437
Signed-off-by: Kerry Sheh <kerry.she@amd.com>
Signed-off-by: Kerry Sheh <shekairui@gmail.com>
Reviewed-on: http://review.coreboot.org/232
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marcj303@gmail.com>