pinctrl: armada-37xx: Fix irq mask access in armada_37xx_irq_set_type()

As explained in the following commit a9a1a483 ("pinctrl:
armada-37xx: Fix gpio interrupt setup") the armada_37xx_irq_set_type()
function can be called before the initialization of the mask field.

That means that we can't use this field in this function and need to
workaround it using hwirq.

Fixes: 30ac0d3b ("pinctrl: armada-37xx: Add edge both type gpio irq support")
Cc: stable@vger.kernel.org
Reported-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20191115155752.2562-1-gregory.clement@bootlin.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/mvebu/pinctrl-armada-37xx.c

@@ -595,10 +595,10 @@ static int armada_37xx_irq_set_type(struct irq_data *d, unsigned int type)
 		regmap_read(info->regmap, in_reg, &in_val);
 
 		/* Set initial polarity based on current input level. */
-		if (in_val & d->mask)
-			val |= d->mask;		/* falling */
+		if (in_val & BIT(d->hwirq % GPIO_PER_REG))
+			val |= BIT(d->hwirq % GPIO_PER_REG);	/* falling */
 		else
-			val &= ~d->mask;	/* rising */
+			val &= ~(BIT(d->hwirq % GPIO_PER_REG));	/* rising */
 		break;
 	}
 	default: