mariadb: fix multiple outputs on darwin

pkgs/servers/sql/mariadb/default.nix

@@ -93,6 +93,12 @@ stdenv.mkDerivation rec {
     mv $out/lib $lib
     mv $out/include $lib
 
+    # Fix library rpaths
+    # TODO: put this in the stdenv to prepare for wide usage of multi-output derivations
+    for file in $(grep -rl $out/lib $lib); do
+      install_name_tool -delete_rpath $out/lib -add_rpath $lib $file
+    done
+
     # Fix the mysql_config
     sed -i $out/bin/mysql_config \
       -e 's,-lz,-L${zlib}/lib -lz,g' \