XXXX don't fail device detach when it's physically removed

@@ -16,15 +16,20 @@
  * fields enclosed by brackets "[]" replaced with your own identifying
  * information: Portions Copyright [yyyy] [name of copyright owner]
  *
  * CDDL HEADER END
  */
+
 /*
  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
+/*
+ * Copyright 2018 Nexenta Systems, Inc.
+ */
+
 #ifndef _SYS_DV_NODE_H
 #define _SYS_DV_NODE_H
 
 /*
  * dv_nodes are the file-system specific part of the

@@ -108,10 +113,11 @@
 
 /* flags for devfs_clean() */
 #define DV_CLEAN_FORCE  0x01    /* force clean of refed directories */
 #define DV_RESET_PERM   0x02    /* force resetting of node permission */
 #define DV_CLEANDIR_LCK 0x04    /* dv_contents already held */
+#define DV_DEVI_GONE    0x08    /* force clean of refed files */
 
 struct devfs_data {
         struct  dv_node *devfs_root;
         struct  vfs     *devfs_vfsp;
 };