ARM: at91/at91sam9x5cm: add 1-wire chip on CM board

This add the 1-wire chip present on the CM board to the DTS.
As the pin is also used by leds, it's disabled by default.
If the board really wants it, it can be enabled in the board DTS.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>