CA-141364: Remove redundant (and erroneous bindings)

We no longer need these bindings since this work is done in Xenguest. Also, it
appears both of the bindings mistakenly make the same call into libxc.

Signed-off-by: Si Beaumont <simon.beaumont@citrix.com>
Merge pull request #166 from simonjbeaumont/ca-141364-xs64bit

[xs64bit] CA-141364: Remove redundant (and erroneous bindings)