powerpc/85xx: Fix USB protocol definitions for P1020RDB

USB protocol macros (CONFIG_USB_EHCI ...) to be included only when
CONFIG_HAS_FSL_DR_USB is defined for a board. Presence of USB DR controller
should be declared along with the underlying protocol used in the controller

Signed-off-by: Ramneek Mehresh <ramneek.mehresh@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>