Bug 1471131 - Fix compiling error of Trampoline on mips. r=jandem

js/src/jit/mips32/Trampoline-mips32.cpp

@@ -758,7 +758,6 @@ JitRuntime::generateVMWrapper(JSContext* cx, MacroAssembler& masm, const VMFunct
 
     // Copy any arguments.
     for (uint32_t explicitArg = 0; explicitArg < f.explicitArgs; explicitArg++) {
-        MoveOperand from;
         switch (f.argProperties(explicitArg)) {
           case VMFunction::WordByValue:
             masm.passABIArg(MoveOperand(argsBase, argDisp), MoveOp::GENERAL);

js/src/jit/mips64/Trampoline-mips64.cpp

@@ -725,7 +725,6 @@ JitRuntime::generateVMWrapper(JSContext* cx, MacroAssembler& masm, const VMFunct
 
     // Copy any arguments.
     for (uint32_t explicitArg = 0; explicitArg < f.explicitArgs; explicitArg++) {
-        MoveOperand from;
         switch (f.argProperties(explicitArg)) {
           case VMFunction::WordByValue:
             if (f.argPassedInFloatReg(explicitArg))