Update op_isinf.cpp

Author: malfet

kernels/portable/cpu/op_isinf.cpp

@@ -14,13 +14,8 @@ namespace torch {
 namespace executor {
 namespace native {
 
-namespace {
-bool isinf(double x) {
-  return ::std::isinf(x);
-}
-}
 Tensor& isinf_out(RuntimeContext& ctx, const Tensor& in, Tensor& out) {
-  return internal::unary_ufunc_realhb_to_bool(isinf, ctx, in, out);
+  return internal::unary_ufunc_realhb_to_bool([](double x) {return std::isinf(x); }, ctx, in, out);
 }
 
 } // namespace native