ARM: at91/DT: add NAND + DMA property

Add the "atmel,nand-has-dma" property to NAND node for SoC that
can use the DMA to perform NAND accesses.
Use of this property was added in 1b7192658a08f70df0f290634fd7cd2ecb629fc9
(mtd: atmel_nand: add a new dt binding item for nand dma support).

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Boris BREZILLON <b.brezillon@overkiz.com>
ARM: at91/DT: atmel_usba correct atmel,vbus-gpio meaning

atmel,at91sam9rl-udc is a USB gadget, it has no means to control vbus.
atmel,vbus-gpio is in fact used to detect the presence of vbus.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
[nicolas.ferre@atmel.com: modify the commit message]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>