Migrate CAN bus HAL to nested namespaces

Test: it builds
Change-Id: I83d9ef4f1fff1585e6487c95f09b55b1aa5b3e63
diff --git a/automotive/can/1.0/default/CanBusSlcan.h b/automotive/can/1.0/default/CanBusSlcan.h
index 2713da8..3328a9f 100644
--- a/automotive/can/1.0/default/CanBusSlcan.h
+++ b/automotive/can/1.0/default/CanBusSlcan.h
@@ -22,12 +22,7 @@
 #include <termios.h>
 #include "CanBus.h"
 
-namespace android {
-namespace hardware {
-namespace automotive {
-namespace can {
-namespace V1_0 {
-namespace implementation {
+namespace android::hardware::automotive::can::V1_0::implementation {
 
 struct CanBusSlcan : public CanBus {
     CanBusSlcan(const std::string& uartName, uint32_t bitrate);
@@ -42,9 +37,4 @@
     base::unique_fd mFd;
 };
 
-}  // namespace implementation
-}  // namespace V1_0
-}  // namespace can
-}  // namespace automotive
-}  // namespace hardware
-}  // namespace android
+}  // namespace android::hardware::automotive::can::V1_0::implementation