Fix Spec.Lib.IntBuf.fst to match its interface
Fix Spec.Lib.IntBuf.fst to match its interface

mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star,mitls/hacl-star