pinctrl: at91: copy define to driver

The #define for the maximum number of GPIO blocks was retrieved
into pinctrl-at91.c by implicit inclusion of <mach/gpio.h>
from <linux/gpio.h> creating a dependency on machine-local
<mach/gpio.h>. Break the depenency by copying this single
define into the driver.
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-at91.c

@@ -33,6 +33,7 @@
 
 #include "core.h"
 
+#define MAX_GPIO_BANKS		5
 #define MAX_NB_GPIO_PER_BANK	32
 
 struct at91_pinctrl_mux_ops;