Fix 64 bit build on FreeBSD. 32 bit build is still borked.

Review URL: http://codereview.chromium.org/7229008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8382 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

SConstruct

@@ -712,6 +712,9 @@ PREPARSER_FLAGS = {
       'CCFLAGS':      ['-g', '-O0'],
       'CPPDEFINES':   ['DEBUG']
     },
+    'os:freebsd': {
+      'LIBPATH' : ['/usr/local/lib'],
+    },
   },
   'msvc': {
     'all': {