Stefan Fiedler:

package/base/device-mapper/device-mapper.conf

@@ -1,3 +1,4 @@
+#!/bin/bash
 # --- ROCK-COPYRIGHT-NOTE-BEGIN ---
 # 
 # This copyright note is auto-generated by ./scripts/Create-CopyPatch.
@@ -30,5 +31,5 @@ devicemapper_pm() {
 }
 
 srcdir="device-mapper.$ver"
-[ "$root/$prefix" = "/usr" ] && confopt=""
+libdir="$root/$multilib"
 postmake="devicemapper_pm"