trans.c (create_temporary): New function taken from...
* gcc-interface/trans.c (create_temporary): New function taken from...
(create_init_temporary): ...here. Call it.
(call_to_gnu): Create the temporary for the return value early, if any.
Create it for a function with copy-in/copy-out parameters if there is
no target; in other cases of copy-in/copy-out, use another temporary.
Push the new binding level lazily. Add and rename local variables.