[dunecontrol,release] Support multiarch detection with clang

clang does not support -print-multiarch. Therefore we try to
extract the "Target:" line from clang -v.

bin/dunecontrol

@@ -244,7 +244,10 @@ extract_multiarch(){
   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/")
+    for i in "target=" "Target:"; do
+      multiarch=$($my_cxx_compiler -v 2>&1| $GREP "$i" | $SED "s/.*$i[$BLANK]*\([a-z0-9_-]*\)/\1/" | $SED "s/-[a-z]*-linux-gnu/-linux-gnu/")
+     if test -n "$multiarch"; then break; fi
+   done
   fi
   set -e # set to old value.
   export MULTIARCH_LIBDIR="lib/$multiarch"

lib/dunemodules.lib

@@ -171,7 +171,10 @@ 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/")
+    for i in "target=" "Target:"; do
+      multiarch=$($my_cxx_compiler -v 2>&1| $GREP "$i" | sed "s/.*$i[$BLANK]*\([a-z0-9_-]*\)/\1/" | $SED "s/-[a-z]*-linux-gnu/-linux-gnu/")
+     if test -n "$multiarch"; then break; fi
+   done
   fi
   set -e # set to old value.
   export MULTIARCH_LIBDIR="lib/$multiarch"