Nest some more namespaces

Did someone previously suggest that all namespace had been
nested?  Silly.

Signed-off-by: Stephan Pleines <pleines.stephan@gmail.com>
Change-Id: I22278c1caaeba8b47dc46fb2ed3078c20a11e190
diff --git a/frc971/control_loops/coerce_goal.h b/frc971/control_loops/coerce_goal.h
index 6867540..3d34e94 100644
--- a/frc971/control_loops/coerce_goal.h
+++ b/frc971/control_loops/coerce_goal.h
@@ -5,8 +5,7 @@
 
 #include "frc971/control_loops/polytope.h"
 
-namespace frc971 {
-namespace control_loops {
+namespace frc971::control_loops {
 
 template <typename Scalar = double>
 Eigen::Matrix<Scalar, 2, 1> DoCoerceGoal(
@@ -127,7 +126,6 @@
   }
 }
 
-}  // namespace control_loops
-}  // namespace frc971
+}  // namespace frc971::control_loops
 
 #endif  // FRC971_CONTROL_LOOPS_COERCE_GOAL_H_