pinctrl: fixup problematic flag

This removes the set_irq_flags() call that unfortunately slipped
into the BCM NSP driver.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yendapally Reddy Dhananjaya Reddy <yrdreddy@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/bcm/pinctrl-nsp-gpio.c

@@ -696,7 +696,6 @@ static int nsp_gpio_probe(struct platform_device *pdev)
 
 			irq_set_chip_and_handler(irq, &nsp_gpio_irq_chip,
 						 handle_simple_irq);
-			set_irq_flags(irq, IRQF_VALID);
 			irq_set_chip_data(irq, chip);
 		}