ansible: turn on arg refurbishing

Fixes Homebrew/homebrew#27639.

Formula/ansible.rb

@@ -48,6 +48,12 @@ class Ansible < Formula
     ENV.prepend_create_path 'PYTHONPATH', libexec+'lib/python2.7/site-packages'
     install_args = [ "setup.py", "install", "--prefix=#{libexec}" ]
 
+    # pycrypto's C bindings use flags unrecognized by clang,
+    # but since it doesn't use a makefile arg refurbishment
+    # is normally not enabled.
+    # See https://github.com/Homebrew/homebrew/issues/27639
+    ENV.append 'HOMEBREW_CCCFG', 'O'
+
     resource('pycrypto').stage { system "python", *install_args }
     resource('pyyaml').stage { system "python", *install_args }
     resource('paramiko').stage { system "python", *install_args }