api: remove HostConfig.LxcConf field
Commit 3b5fac462d21ca164b3778647420016315289034 / docker 1.10 removed support
for the LXC runtime, and removed the corresponding fields from the API (v1.22).
This patch removes the `HostConfig.LxcConf` field from the swagger definition.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Sebastiaan van Stijn