PPC/S390: [es6] Reintroduce the instanceof operator in the backends.

src/ppc/interface-descriptors-ppc.cc

Index: src/ppc/interface-descriptors-ppc.cc
diff --git a/src/ppc/interface-descriptors-ppc.cc b/src/ppc/interface-descriptors-ppc.cc
index caf95449594be29882831b9b45d3def3e8b740ce..64263165ac8615b17b373c7cce9f0a586079ef66 100644
--- a/src/ppc/interface-descriptors-ppc.cc
+++ b/src/ppc/interface-descriptors-ppc.cc
@@ -46,10 +46,6 @@ const Register StoreGlobalViaContextDescriptor::SlotRegister() { return r5; }
 const Register StoreGlobalViaContextDescriptor::ValueRegister() { return r3; }
 
 
-const Register InstanceOfDescriptor::LeftRegister() { return r4; }
-const Register InstanceOfDescriptor::RightRegister() { return r3; }
-
-
 const Register StringCompareDescriptor::LeftRegister() { return r4; }
 const Register StringCompareDescriptor::RightRegister() { return r3; }