volume_id: Add support for UBIFS

Signed-off-by: Serj Kalichev <serj.kalichev@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

util-linux/volume_id/get_devname.c

@@ -107,7 +107,11 @@ uuidcache_check_device(const char *device,
 		int depth UNUSED_PARAM)
 {
 	/* note: this check rejects links to devices, among other nodes */
-	if (!S_ISBLK(statbuf->st_mode))
+	if (!S_ISBLK(statbuf->st_mode)
+#if ENABLE_FEATURE_VOLUMEID_UBIFS
+	 && !(S_ISCHR(statbuf->st_mode) && strncmp(bb_basename(device), "ubi", 3) == 0)
+#endif
+	)
 		return TRUE;
 
 	/* Users report that mucking with floppies (especially non-present