media: i2c: ov4689: Drop check for reentrant .s_stream()

The subdev .s_stream() operation shall not be called to start streaming
on an already started subdev, or stop streaming on a stopped subdev.
Remove the check that guards against that condition.

The streaming field of the driver's private structure is now unused,
drop it as well.

Signed-off-by: Laurent Pinchart <[e-mail]>
Reviewed-by: Mikhail Rudenko <[e-mail]>
[Sakari Ailus: remove now-redundant "streaming" from comment.]
Signed-off-by: Sakari Ailus <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>

drivers/media/i2c/ov4689.c

···
 
 	u32 clock_rate;
 
-	struct mutex mutex; /* lock to protect streaming, ctrls and cur_mode */
-	bool streaming;
+	struct mutex mutex; /* lock to protect ctrls and cur_mode */
 	struct v4l2_ctrl_handler ctrl_handler;
 	struct v4l2_ctrl *exposure;
 
···
 
 	mutex_lock(&ov4689->mutex);
 
-	on = !!on;
-	if (on == ov4689->streaming)
-		goto unlock_and_return;
-
 	if (on) {
 		ret = pm_runtime_resume_and_get(&client->dev);
 		if (ret < 0)
···
 				 OV4689_MODE_SW_STANDBY);
 		pm_runtime_put(&client->dev);
 	}
-
-	ov4689->streaming = on;
 
 unlock_and_return:
 	mutex_unlock(&ov4689->mutex);