Fix for reoder program unit test when built without suitesparse

This commit fixes failure of reorder_program_test when Ceres is built without
any suitesparse.

Change-Id: Ia23ae8dfd20c482cb9cd1301f17edf9a34df3235

internal/ceres/reorder_program_test.cc

diff --git a/internal/ceres/reorder_program_test.cc b/internal/ceres/reorder_program_test.cc
index 5c0d516..661c86c 100644
--- a/internal/ceres/reorder_program_test.cc
+++ b/internal/ceres/reorder_program_test.cc
@@ -169,7 +169,7 @@
   EXPECT_EQ(parameter_blocks[2]->user_state(), &y);
 }
 
-
+#ifndef CERES_NO_SUITESPARSE
 class ReorderProgramForSparseNormalCholeskyUsingSuiteSparseTest : public ::testing::Test {
  protected:
   void SetUp() {
@@ -243,6 +243,7 @@
 
   ComputeAndValidateOrdering(linear_solver_ordering);
 }
+#endif  // CERES_NO_SUITESPARSE
 
 }  // namespace internal
 }  // namespace ceres