Fix the Ceres Android NDK build.

The NDK build of Ceres was broken; this fixes it and also
disables a useless warning that shows up in NDK 8b.

Change-Id: I54cfb3de7ccea4a0864385f7ffdb55d8f3431f34
diff --git a/internal/ceres/solver_impl.cc b/internal/ceres/solver_impl.cc
index 56295ae..64e0f8e 100644
--- a/internal/ceres/solver_impl.cc
+++ b/internal/ceres/solver_impl.cc
@@ -817,7 +817,7 @@
 #endif
 
 #if defined(CERES_NO_SUITESPARSE) && defined(CERES_NO_CXSPARSE)
-  if (linear_solver_options.type == SPARSE_SCHUR) {
+  if (options->linear_solver_type == SPARSE_SCHUR) {
     *error = "Can't use SPARSE_SCHUR because neither SuiteSparse nor"
         "CXSparse was enabled when Ceres was compiled.";
     return NULL;