[turbofan] Fix typing for NumberMin and NumberMax to handle uninhabited types.

test/mjsunit/compiler/regress-700883.js

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+function add(x) {
+ return x + x;
+}
+
+add(0);
+add(1);
+%SetForceInlineFlag(add);
+
+var min = Math.min;
+function foo(x) {
+ x = x|0;
+ let y = add(x ? 800000000000 : NaN);
+ return min(y, x);
+}
+
+%OptimizeFunctionOnNextCall(foo);
+foo();