[intrinsics] Drop the now obsolete %_DoubleHi and %_DoubleLo intrinsics.

src/crankshaft/x64/lithium-x64.cc

Index: src/crankshaft/x64/lithium-x64.cc
diff --git a/src/crankshaft/x64/lithium-x64.cc b/src/crankshaft/x64/lithium-x64.cc
index 01b9918d3181496689196ba17654a52f22872fa2..d0547ee49215d362483b7e45140dc4c70b189099 100644
--- a/src/crankshaft/x64/lithium-x64.cc
+++ b/src/crankshaft/x64/lithium-x64.cc
@@ -1967,13 +1967,6 @@ LInstruction* LChunkBuilder::DoClampToUint8(HClampToUint8* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoDoubleBits(HDoubleBits* instr) {
-  HValue* value = instr->value();
-  DCHECK(value->representation().IsDouble());
-  return DefineAsRegister(new(zone()) LDoubleBits(UseRegister(value)));
-}
-
-
 LInstruction* LChunkBuilder::DoReturn(HReturn* instr) {
   LOperand* context = info()->IsStub() ? UseFixed(instr->context(), rsi) : NULL;
   LOperand* parameter_count = UseRegisterOrConstant(instr->parameter_count());