Migrate CAN bus HAL to nested namespaces

Test: it builds
Change-Id: I83d9ef4f1fff1585e6487c95f09b55b1aa5b3e63
diff --git a/automotive/can/1.0/default/libnetdevice/NetlinkRequest.cpp b/automotive/can/1.0/default/libnetdevice/NetlinkRequest.cpp
index 9845bc7..556debf 100644
--- a/automotive/can/1.0/default/libnetdevice/NetlinkRequest.cpp
+++ b/automotive/can/1.0/default/libnetdevice/NetlinkRequest.cpp
@@ -18,9 +18,7 @@
 
 #include <android-base/logging.h>
 
-namespace android {
-namespace netdevice {
-namespace impl {
+namespace android::netdevice::impl {
 
 static struct rtattr* nlmsg_tail(struct nlmsghdr* n) {
     return reinterpret_cast<struct rtattr*>(  //
@@ -53,6 +51,4 @@
     nest->rta_len = nestLen;
 }
 
-}  // namespace impl
-}  // namespace netdevice
-}  // namespace android
+}  // namespace android::netdevice::impl