drm/bridge: anx7625: fix not correct return value

At some time, the original code may return non zero value, force return 0
if operation finished.
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Xin Ji <xji@analogixsemi.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211104033609.2634452-1-xji@analogixsemi.com

drivers/gpu/drm/bridge/analogix/anx7625.c

@@ -191,10 +191,10 @@ static int wait_aux_op_finish(struct anx7625_data *ctx)
 			       AP_AUX_CTRL_STATUS);
 	if (val < 0 || (val & 0x0F)) {
 		DRM_DEV_ERROR(dev, "aux status %02x\n", val);
-		val = -EIO;
+		return -EIO;
 	}
 
-	return val;
+	return 0;
 }
 
 static int anx7625_video_mute_control(struct anx7625_data *ctx,