ARM: at91: dt: Remove init_time definitions

The current AT91 DT boards have a completely generic init_time definition.
Remove them from the machine declaration.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Conflicts:
	arch/arm/mach-at91/board-dt-sam9.c
	arch/arm/mach-at91/board-dt-sama5.c