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/peripheral/adc.h b/motors/peripheral/adc.h
index c22a856..22db93a 100644
--- a/motors/peripheral/adc.h
+++ b/motors/peripheral/adc.h
@@ -5,8 +5,7 @@
 
 #include "motors/util.h"
 
-namespace frc971 {
-namespace motors {
+namespace frc971::motors {
 
 enum class AdcChannels {
   kA,
@@ -15,7 +14,6 @@
 void AdcInitCommon(AdcChannels adc0_channels = AdcChannels::kB,
                    AdcChannels adc1_channels = AdcChannels::kB);
 
-}  // namespace motors
-}  // namespace frc971
+}  // namespace frc971::motors
 
 #endif  // MOTORS_PERIPHERAL_ADC_H_
diff --git a/motors/peripheral/adc_dma.h b/motors/peripheral/adc_dma.h
index a00b730..f04f5ce 100644
--- a/motors/peripheral/adc_dma.h
+++ b/motors/peripheral/adc_dma.h
@@ -9,8 +9,7 @@
 #include "motors/peripheral/configuration.h"
 #include "motors/util.h"
 
-namespace frc971 {
-namespace teensy {
+namespace frc971::teensy {
 
 // This class manages configuring the hardware to automatically capture various
 // sensor values periodically with tight timing. Currently it's only 4 samples
@@ -108,7 +107,6 @@
   ::std::array<volatile uint32_t *, 2> ftm_delays_{nullptr, nullptr};
 };
 
-}  // namespace teensy
-}  // namespace frc971
+}  // namespace frc971::teensy
 
 #endif  // MOTORS_PERIPHERAL_ADC_DMA_H_
diff --git a/motors/peripheral/spi.h b/motors/peripheral/spi.h
index f865703..c5a1b64 100644
--- a/motors/peripheral/spi.h
+++ b/motors/peripheral/spi.h
@@ -7,8 +7,7 @@
 #include "motors/peripheral/uart_buffer.h"
 #include "motors/util.h"
 
-namespace frc971 {
-namespace teensy {
+namespace frc971::teensy {
 
 // Simple synchronous interface to a SPI peripheral.
 class Spi {
@@ -112,7 +111,6 @@
   int frames_to_receive_ = 0;
 };
 
-}  // namespace teensy
-}  // namespace frc971
+}  // namespace frc971::teensy
 
 #endif  // MOTORS_PERIPHERAL_SPI_H_
diff --git a/motors/peripheral/uart.h b/motors/peripheral/uart.h
index bfd630b..f8e7e7e 100644
--- a/motors/peripheral/uart.h
+++ b/motors/peripheral/uart.h
@@ -8,8 +8,7 @@
 #include "motors/peripheral/uart_buffer.h"
 #include "motors/util.h"
 
-namespace frc971 {
-namespace teensy {
+namespace frc971::teensy {
 
 // Simple synchronous interface to a UART.
 class Uart {
@@ -121,7 +120,6 @@
   UartBuffer<1024> transmit_buffer_, receive_buffer_;
 };
 
-}  // namespace teensy
-}  // namespace frc971
+}  // namespace frc971::teensy
 
 #endif  // MOTORS_PERIPHERAL_UART_H_
diff --git a/motors/peripheral/uart_buffer.h b/motors/peripheral/uart_buffer.h
index 9266465..714cfe8 100644
--- a/motors/peripheral/uart_buffer.h
+++ b/motors/peripheral/uart_buffer.h
@@ -6,8 +6,7 @@
 
 #include "absl/types/span.h"
 
-namespace frc971 {
-namespace teensy {
+namespace frc971::teensy {
 
 // Manages a circular buffer of data to send out.
 template <int kSize>
@@ -90,7 +89,6 @@
   ++size_;
 }
 
-}  // namespace teensy
-}  // namespace frc971
+}  // namespace frc971::teensy
 
 #endif  // MOTORS_PERIPHERAL_UART_BUFFER_H_