gpio: omap: get rid of GPIO_BIT() macro

Now OMAP GPIO driver prepared for GPIO_BIT() macro removing.
Do it ;)
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Acked-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-omap.c

@@ -82,7 +82,6 @@ struct gpio_bank {
 };
 
 #define GPIO_INDEX(bank, gpio) (gpio % bank->width)
-#define GPIO_BIT(bank, gpio) (BIT(GPIO_INDEX(bank, gpio)))
 #define GPIO_MOD_CTRL_BIT	BIT(0)
 
 #define BANK_USED(bank) (bank->mod_usage || bank->irq_usage)