MIPS: Fix deoptimization failure in WordCompare

src/full-codegen/mips64/full-codegen-mips64.cc

Index: src/full-codegen/mips64/full-codegen-mips64.cc
diff --git a/src/full-codegen/mips64/full-codegen-mips64.cc b/src/full-codegen/mips64/full-codegen-mips64.cc
index 8096d6f87b79327054f49139aa4a0bfb79d93713..d81d142aa705f33b766c742993d439aa84d801a7 100644
--- a/src/full-codegen/mips64/full-codegen-mips64.cc
+++ b/src/full-codegen/mips64/full-codegen-mips64.cc
@@ -735,7 +735,7 @@ void FullCodeGenerator::PrepareForBailoutBeforeSplit(Expression* expr,
   PrepareForBailout(expr, BailoutState::TOS_REGISTER);
   if (should_normalize) {
     __ LoadRoot(a4, Heap::kTrueValueRootIndex);
-    Split(eq, a0, Operand(a4), if_true, if_false, NULL);
+    Split(eq, v0, Operand(a4), if_true, if_false, NULL);
     __ bind(&skip);
   }
 }