ARM: at91: dt: enable usb ohci for sam9g20, sam9g45 amd sam9x5

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: devicetree-discuss@lists.ozlabs.org