i2c: mux: demux-pinctrl: disable PM user interface

The demux device is only a logical device with no children. So, no
RuntimePM is needed, let's disable the sysfs interface for it.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NPeter Rosin <peda@axentia.se>

drivers/i2c/muxes/i2c-demux-pinctrl.c

@@ -18,6 +18,7 @@
 #include <linux/of.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
 
@@ -254,6 +255,8 @@ static int i2c_demux_pinctrl_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, priv);
 
+	pm_runtime_no_callbacks(&pdev->dev);
+
 	/* switch to first parent as active master */
 	i2c_demux_activate_master(priv, 0);