fix: the total used vnode number not increased after unlink a file under

/dev/

fix #I3TS1Y
Signed-off-by: yansira <yansira@hotmail.com>

fs/vfs/vnode.c

@@ -642,6 +642,7 @@ int VnodeDestory(struct Vnode *vnode)
 
     free(vnode->data);
     free(vnode);
+    g_totalVnodeSize--;
     VnodeDrop();
 
     return LOS_OK;