[stubs] Port LoadFunctionPrototypeStub to CSA

src/s390/macro-assembler-s390.h

Index: src/s390/macro-assembler-s390.h
diff --git a/src/s390/macro-assembler-s390.h b/src/s390/macro-assembler-s390.h
index dba1c938cb09702e261a4f5e937481141edbe710..d5954057fce80f3bd9fd213ec7cb498ed44328ae 100644
--- a/src/s390/macro-assembler-s390.h
+++ b/src/s390/macro-assembler-s390.h
@@ -1061,14 +1061,6 @@ class MacroAssembler : public Assembler {
   void GetMapConstructor(Register result, Register map, Register temp,
                          Register temp2);
 
-  // Try to get function prototype of a function and puts the value in
-  // the result register. Checks that the function really is a
-  // function and jumps to the miss label if the fast checks fail. The
-  // function register will be untouched; the other registers may be
-  // clobbered.
-  void TryGetFunctionPrototype(Register function, Register result,
-                               Register scratch, Label* miss);
-
   // Compare object type for heap object.  heap_object contains a non-Smi
   // whose object type should be compared with the given type.  This both
   // sets the flags and leaves the object type in the type_reg register.