pinctrl: armada-37xx: Fix spurious irq management

Until now, if we found spurious irq in irq_handler, we only updated the
status in register but not the status in the code. Due to this the system
will got stuck dues to the infinite loop

[gregory.clement@bootlin.com: update comment and add fix and stable tags]
Fixes: 30ac0d3b ("pinctrl: armada-37xx: Add edge both type gpio irq support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Terry Zhou <bjzhou@marvell.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>