Revert of [turbofan] Add the StackSlot operator to turbofan.

src/compiler/raw-machine-assembler.h

Index: src/compiler/raw-machine-assembler.h
diff --git a/src/compiler/raw-machine-assembler.h b/src/compiler/raw-machine-assembler.h
index c4c981c1a51babc87418d9f78c347c98f293384a..b324828188fa54ce7e64a73e09d0f8198cafcc8d 100644
--- a/src/compiler/raw-machine-assembler.h
+++ b/src/compiler/raw-machine-assembler.h
@@ -78,9 +78,6 @@
   }
   Node* Int32Constant(int32_t value) {
     return AddNode(common()->Int32Constant(value));
-  }
-  Node* StackSlot(MachineRepresentation rep) {
-    return AddNode(machine()->StackSlot(rep));
   }
   Node* Int64Constant(int64_t value) {
     return AddNode(common()->Int64Constant(value));