[flang] silence a warning

Original-commit: flang-compiler/f18@dc91727ac4
Reviewed-on: https://github.com/flang-compiler/f18/pull/73
Tree-same-pre-rewrite: false

flang/lib/semantics/resolve-names.cc

@@ -644,6 +644,7 @@ KindParamValue DeclTypeSpecVisitor::GetKindParamValue(
     return KindParamValue(std::get<std::uint64_t>(intlit.t));
   } else {
     CHECK(!"TODO: translate star-size to kind");
+    return {};  // silence compiler warning
   }
 }