[turbofan] Remove Instruction::IsControl() and Instruction::MarkAsControl()

test/cctest/compiler/test-jump-threading.cc

Index: test/cctest/compiler/test-jump-threading.cc
diff --git a/test/cctest/compiler/test-jump-threading.cc b/test/cctest/compiler/test-jump-threading.cc
index 73a464e8dcae03e8b8b3df8aa1619b46d7ee4877..b2d3008aa9322ef48498bc256df6fef5520a72f4 100644
--- a/test/cctest/compiler/test-jump-threading.cc
+++ b/test/cctest/compiler/test-jump-threading.cc
@@ -30,8 +30,8 @@ class TestCode : public HandleAndZoneScope {
   int Jump(int target) {
     Start();
     InstructionOperand ops[] = {UseRpo(target)};
-    sequence_.AddInstruction(Instruction::New(main_zone(), kArchJmp, 0, NULL, 1,
-                                              ops, 0, NULL)->MarkAsControl());
+    sequence_.AddInstruction(
+        Instruction::New(main_zone(), kArchJmp, 0, NULL, 1, ops, 0, NULL));
     int pos = static_cast<int>(sequence_.instructions().size() - 1);
     End();
     return pos;
@@ -45,8 +45,8 @@ class TestCode : public HandleAndZoneScope {
     InstructionOperand ops[] = {UseRpo(ttarget), UseRpo(ftarget)};
     InstructionCode code = 119 | FlagsModeField::encode(kFlags_branch) |
                            FlagsConditionField::encode(kEqual);
-    sequence_.AddInstruction(Instruction::New(main_zone(), code, 0, NULL, 2,
-                                              ops, 0, NULL)->MarkAsControl());
+    sequence_.AddInstruction(
+        Instruction::New(main_zone(), code, 0, NULL, 2, ops, 0, NULL));
     int pos = static_cast<int>(sequence_.instructions().size() - 1);
     End();
     return pos;