pwm: Mention PWM chip ID in /sys/kernel/debug/pwm

While it's not hard to match the entries from /sys/kernel/debug/pwm to
the corresponding pwmchip in /sys/class/pwm, it's a bit simpler to have
the number mentioned in /sys/kernel/debug/pwm.

Link: https://lore.kernel.org/r/20230808165250.942396-3-u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/core.c

@@ -1062,7 +1062,8 @@ static int pwm_seq_show(struct seq_file *s, void *v)
 {
 	struct pwm_chip *chip = v;
 
-	seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private,
+	seq_printf(s, "%s%d: %s/%s, %d PWM device%s\n",
+		   (char *)s->private, chip->id,
 		   chip->dev->bus ? chip->dev->bus->name : "no-bus",
 		   dev_name(chip->dev), chip->npwm,
 		   (chip->npwm != 1) ? "s" : "");