drivers/video: Update unlink() and video_uninitialize() operation

Add unregister_driver() execution to unlink() operation
to delete device file.
Also, add resource cleanup to video_uninitialize() operation
to avoid memory leak without unlink() execution for compatibility.

drivers/video/video.c

@@ -32,6 +32,8 @@
 #include <assert.h>
 #include <errno.h>
 #include <poll.h>
+#include <sys/stat.h>
+#include <nuttx/fs/fs.h>
 
 #include <nuttx/kmalloc.h>
 #include <nuttx/mutex.h>
@@ -1015,6 +1017,18 @@ static void cleanup_resources(FAR video_mng_t *vmng)
   cleanup_scenes_parameter(vmng);
 }
 
+static void cleanup_private_data(FAR struct inode *inode)
+{
+  FAR video_mng_t *priv = inode->i_private;
+
+  nxmutex_unlock(&priv->lock_open_num);
+  nxmutex_destroy(&priv->lock_open_num);
+  unregister_driver(priv->devpath);
+  kmm_free(priv->devpath);
+  kmm_free(priv);
+  inode->i_private = NULL;
+}
+
 static bool is_sem_waited(FAR sem_t *sem)
 {
   int semcount;
@@ -1094,11 +1108,7 @@ static int video_close(FAR struct file *filep)
 #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
       if (priv->unlinked)
         {
-          nxmutex_unlock(&priv->lock_open_num);
-          nxmutex_destroy(&priv->lock_open_num);
-          kmm_free(priv->devpath);
-          kmm_free(priv);
-          inode->i_private = NULL;
+          cleanup_private_data(inode);
           return OK;
         }
 
@@ -1128,11 +1138,7 @@ static int video_unlink(FAR struct inode *inode)
   nxmutex_lock(&priv->lock_open_num);
   if (priv->open_num == 0)
     {
-      nxmutex_unlock(&priv->lock_open_num);
-      nxmutex_destroy(&priv->lock_open_num);
-      kmm_free(priv->devpath);
-      kmm_free(priv);
-      inode->i_private = NULL;
+      cleanup_private_data(inode);
     }
   else
     {
@@ -3488,7 +3494,16 @@ int video_register(FAR const char *devpath,
 
 int video_unregister(FAR const char *devpath)
 {
-  return unregister_driver(devpath);
+  int ret;
+  struct stat buf;
+
+  ret = nx_stat(devpath, &buf, 1);
+  if (ret == 0)
+    {
+      ret = nx_unlink(devpath);
+    }
+
+  return ret;
 }
 
 int imgsensor_register(FAR struct imgsensor_s *sensor)