[doit][darwin] remove /opt/local/lib from the search path when building

Change-Id: I48d6a150e60d333975a298b91eb97f8523cd9ba6
diff --git a/doit b/doit
index 7446f6c..a053c0d 100755
--- a/doit
+++ b/doit
@@ -92,14 +92,9 @@
     PARALLEL=-j`expr $COUNT + $COUNT`
 fi
 if [ "$OS" = "Darwin" ]; then
-    export CPPFLAGS=-I/opt/local/include
-    export LDFLAGS=-L/opt/local/lib
+    # needed to work around problem with clang compiler and some generated code in gcc
     export CXXFLAGS="-fbracket-depth=1024"
 fi
-if [ "$OS" = "FreeBSD" ]; then
-    export CPPFLAGS=-I/usr/local/include
-    export LDFLAGS=-L/usr/local/lib
-fi
 MAKE=make
 if [ "$OS" = "FreeBSD" ]; then
     MAKE=gmake