pinctrl: sh-pfc: Do not use platform_get_irq() to count interrupts

As platform_get_irq() now prints an error when the interrupt does not
exist, counting interrupts by looping until failure causes the printing
of scary messages like:

    sh-pfc e6060000.pin-controller: IRQ index 0 not found

Fix this by using the platform_irq_count() helper instead.

Fixes: 7723f4c5 ("driver core: platform: Add an error message to platform_get_irq*()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20191016142601.28255-1-geert+renesas@glider.be

drivers/pinctrl/sh-pfc/core.c

@@ -29,12 +29,12 @@
 static int sh_pfc_map_resources(struct sh_pfc *pfc,
 				struct platform_device *pdev)
 {
-	unsigned int num_windows, num_irqs;
 	struct sh_pfc_window *windows;
 	unsigned int *irqs = NULL;
+	unsigned int num_windows;
 	struct resource *res;
 	unsigned int i;
-	int irq;
+	int num_irqs;
 
 	/* Count the MEM and IRQ resources. */
 	for (num_windows = 0;; num_windows++) {
@@ -42,17 +42,13 @@ static int sh_pfc_map_resources(struct sh_pfc *pfc,
 		if (!res)
 			break;
 	}
-	for (num_irqs = 0;; num_irqs++) {
-		irq = platform_get_irq(pdev, num_irqs);
-		if (irq == -EPROBE_DEFER)
-			return irq;
-		if (irq < 0)
-			break;
-	}
-
 	if (num_windows == 0)
 		return -EINVAL;
 
+	num_irqs = platform_irq_count(pdev);
+	if (num_irqs < 0)
+		return num_irqs;
+
 	/* Allocate memory windows and IRQs arrays. */
 	windows = devm_kcalloc(pfc->dev, num_windows, sizeof(*windows),
 			       GFP_KERNEL);