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/motors/usb/queue.h b/motors/usb/queue.h
index f7a7e77..2142213 100644
--- a/motors/usb/queue.h
+++ b/motors/usb/queue.h
@@ -4,8 +4,7 @@
 #include <atomic>
 #include <memory>
 
-namespace frc971 {
-namespace teensy {
+namespace frc971::teensy {
 
 // A FIFO queue which reads/writes variable-sized chunks.
 //
@@ -61,7 +60,6 @@
   ::std::atomic<size_t> write_cursor_{0};
 };
 
-}  // namespace teensy
-}  // namespace frc971
+}  // namespace frc971::teensy
 
 #endif  // MOTORS_USB_QUEUE_H_