staging: greybus: gpio: Use generic_handle_irq_safe().

Instead of manually disabling interrupts before invoking use
generic_handle_irq_safe() which can be invoked with enabled and disabled
interrupts.

Signed-off-by: Sebastian Andrzej Siewior <[e-mail]>
Signed-off-by: Thomas Gleixner <[e-mail]>
Acked-by: Greg Kroah-Hartman <[e-mail]>
Acked-by: Johan Hovold <[e-mail]>
Cc: Alex Elder <[e-mail]>
Cc: Rui Miguel Silva <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/staging/greybus/gpio.c

···
 		return -EINVAL;
 	}
 
-	local_irq_disable();
-	ret = generic_handle_irq(irq);
-	local_irq_enable();
-
+	ret = generic_handle_irq_safe(irq);
 	if (ret)
 		dev_err(dev, "failed to invoke irq handler\n");