On OMAP2+ platforms, USB support needs physical layer signalling and
the NOP USB Transceiver driver since v3.10. This patch enables USB_PHY
and NOP_USB_XCEIV in omap2plus_defconfig. These two are harmless to
the kernel stability, and useful since they are required for USB and
Ethernet (over USB) support.

We do not enable USB_EHCI_HCD here because all features aren't fully
supported yet.

This patch applies to Linux 3.10-rc3.

Cc: Roger Quadros <rogerq@ti.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Adrien Vergé <adrienverge@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>