A64: Replace a Subs by a Sub where flags don't need to be updated.

src/a64/code-stubs-a64.cc

Index: src/a64/code-stubs-a64.cc
diff --git a/src/a64/code-stubs-a64.cc b/src/a64/code-stubs-a64.cc
index da5b4aeda39bce3921168c6bf63ca43b458397fa..6dd4558562da1ee01748870c417e4fad80532dcb 100644
--- a/src/a64/code-stubs-a64.cc
+++ b/src/a64/code-stubs-a64.cc
@@ -3640,10 +3640,9 @@ void ICCompareStub::GenerateSmis(MacroAssembler* masm) {
   // Bail out (to 'miss') unless both x0 and x1 are smis.
   __ JumpIfEitherNotSmi(x0, x1, &miss);
 
-  // TODO(jbramley): Why do we only set the flags for EQ?
   if (GetCondition() == eq) {
     // For equality we do not care about the sign of the result.
-    __ Subs(x0, x0, x1);
+    __ Sub(x0, x0, x1);
   } else {
     // Untag before subtracting to avoid handling overflow.
     __ SmiUntag(x1);