Create a local ipasir solver object, initialize it, and
properly release it when done.
The syntax of with-local-ipasir is similar to that of with-local-stobj, but the first argument (stobj name) is optional and defaults
to ipasir. However, note that state must be available and must be
one of the objects returned by the inner mv-let form; this is because
ipasir-init returns state.
