In 2.7 we will only support the Haskell version, if enabled.

Since the original hconfd enabling was a bit hack-ish (copying over
the actual installed ganeti-confd, Python version), the Makefile.am
changes are a bit more involved than just the removal of the Python
code.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Bernardo Dal Seno <bdalseno@google.com>