Fix unused variable warning in opt build

    TESTED with existing tests

--

PiperOrigin-RevId: 244808731
diff --git a/lib/FxpMathOps/Transforms/UniformKernelUtils.h b/lib/FxpMathOps/Transforms/UniformKernelUtils.h
index 7b25739..f96ee9e 100644
--- a/lib/FxpMathOps/Transforms/UniformKernelUtils.h
+++ b/lib/FxpMathOps/Transforms/UniformKernelUtils.h
@@ -202,6 +202,7 @@
   bool losesInfo;
   auto status = value.convert(ft.getFloatSemantics(),
                               APFloat::rmNearestTiesToEven, &losesInfo);
+  (void)status; // unused in opt mode
   assert((status & (APFloat::opDivByZero | APFloat::opInvalidOp)) == 0 &&
          "could not convert to float const");
   return value;