gpio: mvebu: fix blink counter register selection

The blink counter A was always selected because 0 was forced in the
blink select counter register.
The variable 'set' was obviously there to be used as the register value,
selecting the B counter when id==1 and A counter when id==0.

Tested on clearfog-pro (Marvell 88F6828)

Fixes: 757642f9 ("gpio: mvebu: Add limited PWM support")
Reviewed-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: NRalph Sennhauser <ralph.sennhauser@gmail.com>
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-mvebu.c

@@ -747,7 +747,7 @@ static int mvebu_pwm_probe(struct platform_device *pdev,
 		set = U32_MAX;
 	else
 		return -EINVAL;
-	writel_relaxed(0, mvebu_gpioreg_blink_counter_select(mvchip));
+	writel_relaxed(set, mvebu_gpioreg_blink_counter_select(mvchip));
 
 	mvpwm = devm_kzalloc(dev, sizeof(struct mvebu_pwm), GFP_KERNEL);
 	if (!mvpwm)