pinctrl: at91: add drive strength support for SAM9X60

Add drive strength support for SAM9X60 pin controller.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinctrl-at91.h b/drivers/pinctrl/pinctrl-at91.h
index 79b957f..19fc27e 100644
--- a/drivers/pinctrl/pinctrl-at91.h
+++ b/drivers/pinctrl/pinctrl-at91.h
@@ -69,4 +69,6 @@
 #define AT91SAM9X5_PIO_DRIVER1	0x114  /*PIO Driver 1 register offset*/
 #define AT91SAM9X5_PIO_DRIVER2	0x118  /*PIO Driver 2 register offset*/
 
+#define SAM9X60_PIO_DRIVER1	0x118	/* PIO Driver 1 register offset */
+
 #endif