Remove an unused variable from compressed_row_sparse_matrix.cc

Change-Id: I7786417f99d87382beca7b3d65ef61b7cb5ea3d9
diff --git a/internal/ceres/compressed_row_sparse_matrix.cc b/internal/ceres/compressed_row_sparse_matrix.cc
index ce587da..f2c7747 100644
--- a/internal/ceres/compressed_row_sparse_matrix.cc
+++ b/internal/ceres/compressed_row_sparse_matrix.cc
@@ -660,7 +660,6 @@
       options.min_row_block_size, options.max_row_block_size);
   std::uniform_real_distribution<double> uniform01(0.0, 1.0);
   std::normal_distribution<double> standard_normal_distribution;
-  auto values_dist = std::bind(standard_normal_distribution, std::ref(prng));
 
   // Generate the row block structure.
   for (int i = 0; i < options.num_row_blocks; ++i) {