Fix foreign-funcall sprintf tests' return types.
Fix foreign-funcall sprintf tests' return types.

dochang/cffi,wesen/cffi,dochang/cffi,cffi/cffi,cffi/cffi,kingcheez/cffi-cheez,dkochmanski/cffi,dkochmanski/cffi,3b/cffi,dkochmanski/cffi,kingcheez/cffi-cheez,marsijanin/cffi,stassats/cffi,mcna/cffi,attila-lendvai/cffi,kingcheez/cffi-cheez,3b/cffi,mcna/cffi,akovalenko/cffi,marsijanin/cffi,dochang/cffi,cffi/cffi,attila-lendvai/cffi,3b/cffi,akovalenko/cffi,wesen/cffi,wesen/cffi,stassats/cffi,akovalenko/cffi,marsijanin/cffi,stassats/cffi