[turbofan] Enable tail calls for %_CallFunction.

src/compiler/linkage.h

Index: src/compiler/linkage.h
diff --git a/src/compiler/linkage.h b/src/compiler/linkage.h
index ea130d7ddf1df33cd1d497f3a391864732720e99..e403f63bb14ac890ded2dd295d1131538627a734 100644
--- a/src/compiler/linkage.h
+++ b/src/compiler/linkage.h
@@ -20,6 +20,7 @@ class CallInterfaceDescriptor;
 
 namespace compiler {
 
+class Node;
 class OsrHelper;
 
 // Describes the location for a parameter or a return value to a call.
@@ -167,6 +168,8 @@ class CallDescriptor final : public ZoneObject {
 
   bool HasSameReturnLocationsAs(const CallDescriptor* other) const;
 
+  bool CanTailCall(const Node* call) const;
+
  private:
   friend class Linkage;