i2c: mux: reg: don't log an error for probe deferral

It's possible that i2c_mux_reg_probe_dt() could return -EPROBE_DEFER.
In that case, driver will request a probe deferral and an error
suggesting device tree parsing problem will be reported. This is
a pretty confusing information. Let's change the error handling,
so driver will be able to request probe deferral without logging
not related errors.

Signed-off-by: Tomasz Bachorski <tomasz.bachorski@nokia.com>
Signed-off-by: Peter Rosin <peda@axentia.se>

drivers/i2c/muxes/i2c-mux-reg.c

@@ -177,6 +177,9 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
 			sizeof(mux->data));
 	} else {
 		ret = i2c_mux_reg_probe_dt(mux, pdev);
+		if (ret == -EPROBE_DEFER)
+			return ret;
+
 		if (ret < 0) {
 			dev_err(&pdev->dev, "Error parsing device tree");
 			return ret;