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/wpilib/generic_can_writer.h b/frc971/wpilib/generic_can_writer.h
index 7d6dd1a..d339324 100644
--- a/frc971/wpilib/generic_can_writer.h
+++ b/frc971/wpilib/generic_can_writer.h
@@ -5,8 +5,7 @@
 #include "frc971/wpilib/loop_output_handler.h"
 #include "frc971/wpilib/talonfx.h"
 
-namespace frc971 {
-namespace wpilib {
+namespace frc971::wpilib {
 
 /// This class uses a callback whenever it writes so that the caller can use any
 /// flatbuffer to write to the talonfx motor.
@@ -70,5 +69,4 @@
       write_callback_;
 };
 
-}  // namespace wpilib
-}  // namespace frc971
\ No newline at end of file
+}  // namespace frc971::wpilib