[dunecontrol,bugfix] Changes another sed statement.

This was lost in the last commit.

lib/dunemodules.lib

@@ -171,7 +171,7 @@ extract_multiarch_pkg_config_path(){
   fi
   multiarch=$($my_cxx_compiler --print-multiarch 2>/dev/null)
   if test $? -gt 0; then
-    multiarch=$($my_cxx_compiler -v 2>&1| $GREP target | sed "s/.*target=\([a-z0-9_-]\+\)/\1/")
+    multiarch=$($my_cxx_compiler -v 2>&1| $GREP target | sed "s/.*target=\([a-z0-9_-]*\)/\1/")
   fi
   set -e # set to old value.
   export MULTIARCH_LIBDIR="lib/$multiarch"