[linear_algebra] Remove warnings with Eigen on bionic.

include/dynamic-graph/linear-algebra.h

@@ -6,8 +6,11 @@
 
 #ifndef DYNAMIC_GRAPH_LINEAR_ALGEBRA_H
 #define DYNAMIC_GRAPH_LINEAR_ALGEBRA_H
+#pragma GCC diagnostic push
+#pragma GCC system_header
 #include <Eigen/Core>
 #include <Eigen/Geometry>
+#pragma GCC diagnostic pop
 
 namespace dynamicgraph {
 typedef Eigen::MatrixXd Matrix;