Fix thrift when ghc is installed

Thrift wants to install various language bindings. Per homebrew policy, all of these are by default disabled. However, the Haskell bindings were overlooked, because it does not attempt to build them unless ghc is installed. This commit lets thrift build when the ghc brew is installed.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Formula/thrift.rb

@@ -18,6 +18,7 @@ class Thrift <Formula
     system "./configure", "--disable-debug",
                           "--prefix=#{prefix}",
                           "--libdir=#{lib}",
+                          "--without-haskell",
                           "--without-java",
                           "--without-python",
                           "--without-ruby",