tools: ocaml: remove create_info and build_info data types from xl bindings

tools: ocaml: remove create_info and build_info data types from xl bindings

There are currently no stub functions which use these datatypes. The
existing definitions are out of date wrt the C API (and the conversion
routines are commented out anyway) and are complex from the IDL point
of view (and so will be skipped in the first round of
autogeneration). Remove them to keep things simple for now.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson.citrix.com>
Committed-by: Ian Jackson <ian.jackson.citrix.com>