ARM: at91: dt: at91sam9x5: complete NAND pinctrl

There was only chip enable and readdy/busy pins for the nand controller.
This add the rest of the pins.
pinctrl_nand_16bits contains the specific muxes for 16 bits NANDs.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>