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/input/joystick_input.h b/frc971/input/joystick_input.h
index 074908d..b6d0ceb 100644
--- a/frc971/input/joystick_input.h
+++ b/frc971/input/joystick_input.h
@@ -6,8 +6,7 @@
 #include "aos/events/event_loop.h"
 #include "frc971/input/driver_station_data.h"
 
-namespace frc971 {
-namespace input {
+namespace frc971::input {
 
 // A class for handling joystick packet values.
 // It will call RunIteration each time a new packet is received.
@@ -40,7 +39,6 @@
   int mode_;
 };
 
-}  // namespace input
-}  // namespace frc971
+}  // namespace frc971::input
 
 #endif  // AOS_INPUT_JOYSTICK_INPUT_H_