Remove a little more dead code from lithium-* files.

src/mips/lithium-mips.cc

Index: src/mips/lithium-mips.cc
===================================================================
--- src/mips/lithium-mips.cc	(revision 10556)
+++ src/mips/lithium-mips.cc	(working copy)
@@ -686,12 +686,6 @@
 
 
 template<int I, int T>
-LInstruction* LChunkBuilder::Define(LTemplateInstruction<1, I, T>* instr) {
-  return Define(instr, new LUnallocated(LUnallocated::NONE));
-}
-
-
-template<int I, int T>
 LInstruction* LChunkBuilder::DefineAsRegister(
     LTemplateInstruction<1, I, T>* instr) {
   return Define(instr, new LUnallocated(LUnallocated::MUST_HAVE_REGISTER));