[arm64] cleanup heap numbers detection

src/arm64/lithium-arm64.h

Index: src/arm64/lithium-arm64.h
diff --git a/src/arm64/lithium-arm64.h b/src/arm64/lithium-arm64.h
index 2a64d0635aee3e3c85c67b7dfa2c697384545157..51bfd101eaedf3dfe455eb1d50b027956e692d17 100644
--- a/src/arm64/lithium-arm64.h
+++ b/src/arm64/lithium-arm64.h
@@ -1040,17 +1040,15 @@ class LClampIToUint8 FINAL : public LTemplateInstruction<1, 1, 0> {
 };
 
 
-class LClampTToUint8 FINAL : public LTemplateInstruction<1, 1, 2> {
+class LClampTToUint8 FINAL : public LTemplateInstruction<1, 1, 1> {
  public:
-  LClampTToUint8(LOperand* unclamped, LOperand* temp1, LOperand* temp2) {
+  LClampTToUint8(LOperand* unclamped, LOperand* temp1) {
     inputs_[0] = unclamped;
     temps_[0] = temp1;
-    temps_[1] = temp2;
   }
 
   LOperand* unclamped() { return inputs_[0]; }
   LOperand* temp1() { return temps_[0]; }
-  LOperand* temp2() { return temps_[1]; }
 
   DECLARE_CONCRETE_INSTRUCTION(ClampTToUint8, "clamp-t-to-uint8")
 };