media: rk-isp10: add api mutex for multi-thread app

Change-Id: If2f8600a5f6cdf57bc3859b81a68539bb2d05a84
Signed-off-by: Hu Kejun <william.hu@rock-chips.com>

Author: Hu Kejun

drivers/media/platform/rk-isp10/cif_isp10.h

@@ -674,6 +674,8 @@ struct cif_isp10_device {
 	struct pltfrm_soc_cfg soc_cfg;
 	void *nodes;
 
+	struct mutex api_mutex; /* user api mutex */
+
 };
 
 struct cif_isp10_fmt *get_cif_isp10_output_format(int index);