power: reset: at91-reset: get rid of at91_reset_data

After refactoring struct at91_reset_data and
struct at91_reset_data at91sam9260_reset_data are not needed anymore.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>