[turbofan] Introduce optional Float64Min and Float64Max machine operators.

test/unittests/compiler/machine-operator-unittest.cc

Index: test/unittests/compiler/machine-operator-unittest.cc
diff --git a/test/unittests/compiler/machine-operator-unittest.cc b/test/unittests/compiler/machine-operator-unittest.cc
index fcdb0aeef67414a673d01dc8b6caa47b53bc3f83..8244c3791412b35df3e9250f892491e4ac49548c 100644
--- a/test/unittests/compiler/machine-operator-unittest.cc
+++ b/test/unittests/compiler/machine-operator-unittest.cc
@@ -209,7 +209,8 @@ const PureOperator kPureOperators[] = {
     PURE(Float64RoundTiesAway, 1, 0, 1), PURE(Float64ExtractLowWord32, 1, 0, 1),
     PURE(Float64ExtractHighWord32, 1, 0, 1),
     PURE(Float64InsertLowWord32, 2, 0, 1),
-    PURE(Float64InsertHighWord32, 2, 0, 1)
+    PURE(Float64InsertHighWord32, 2, 0, 1), PURE(Float64Max, 2, 0, 1),
+    PURE(Float64Min, 2, 0, 1)
 #undef PURE
 };