mfd: sun4i-gpadc: Replace irqchip mask_invert with unmask_base

Remove use of the deprecated mask_invert flag. Inverted mask
registers (where a '1' bit enables an IRQ) can be described more
directly as an unmask register.
Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
Reviewed-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221112151835.39059-17-aidanmacdonald.0x0@gmail.com

drivers/mfd/sun4i-gpadc.c

@@ -34,9 +34,8 @@ static const struct regmap_irq_chip sun4i_gpadc_regmap_irq_chip = {
 	.name = "sun4i_gpadc_irq_chip",
 	.status_base = SUN4I_GPADC_INT_FIFOS,
 	.ack_base = SUN4I_GPADC_INT_FIFOS,
-	.mask_base = SUN4I_GPADC_INT_FIFOC,
+	.unmask_base = SUN4I_GPADC_INT_FIFOC,
 	.init_ack_masked = true,
-	.mask_invert = true,
 	.irqs = sun4i_gpadc_regmap_irq,
 	.num_irqs = ARRAY_SIZE(sun4i_gpadc_regmap_irq),
 	.num_regs = 1,