PPC/s390: [ubsan] Use Address parameters for calling generated code

Port 42b4180d

Original Commit Message:

    The simulated C++ signature for generated code entry points should
    rely on primitive values (as opposed to ObjectPtr).

R=jkummerow@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: I55c67e8d42d97b45d5b0eb878ddd6ab3cf872942
Reviewed-on: https://chromium-review.googlesource.com/c/1394755Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#58533}

src/builtins/ppc/builtins-ppc.cc

@@ -537,9 +537,9 @@ namespace {
 // Called with the native C calling convention. The corresponding function
 // signature is:
 //
-//  using JSEntryFunction = GeneratedCode<Object*(
-//      Object * new_target, Object * target, Object * receiver, int argc,
-//      Object*** args, Address root_register_value)>;
+//  using JSEntryFunction = GeneratedCode<Address(
+//      Address new_target, Address target, Address receiver, int argc,
+//      Address** args, Address root_register_value)>;
 void Generate_JSEntryVariant(MacroAssembler* masm, StackFrame::Type type,
                              Builtins::Name entry_trampoline) {
   // r3: code entry

src/builtins/s390/builtins-s390.cc

@@ -537,9 +537,9 @@ namespace {
 // Called with the native C calling convention. The corresponding function
 // signature is:
 //
-//  using JSEntryFunction = GeneratedCode<Object*(
-//      Object * new_target, Object * target, Object * receiver, int argc,
-//      Object*** args, Address root_register_value)>;
+//  using JSEntryFunction = GeneratedCode<Address(
+//      Address new_target, Address target, Address receiver, int argc,
+//      Address** args, Address root_register_value)>;
 void Generate_JSEntryVariant(MacroAssembler* masm, StackFrame::Type type,
                              Builtins::Name entry_trampoline) {
   // r2:                            code entry