[mips] Fix typos introduced by previous commit.

src/mips64/lithium-codegen-mips64.cc

Index: src/mips64/lithium-codegen-mips64.cc
diff --git a/src/mips64/lithium-codegen-mips64.cc b/src/mips64/lithium-codegen-mips64.cc
index 9df5ccaa9992e213367558a885ca42f5ba07ee92..cf8a1aa71513d281e79b21ea788c57ee462ad418 100644
--- a/src/mips64/lithium-codegen-mips64.cc
+++ b/src/mips64/lithium-codegen-mips64.cc
@@ -3876,7 +3876,7 @@ void LCodeGen::DoMathPowHalf(LMathPowHalf* instr) {
   // Math.pow(-Infinity, 0.5) == Infinity
   // Math.sqrt(-Infinity) == NaN
   Label done;
-  __ Move(temp, std::numeric_limits<double>::infinity());
+  __ Move(temp, -std::numeric_limits<double>::infinity());
   __ BranchF(USE_DELAY_SLOT, &done, NULL, eq, temp, input);
   // Set up Infinity in the delay slot.
   // result is overwritten if the branch is not taken.