sensors/zones: place in namespace and cleanup

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I527dbc8477a232945f696227a7b0b2adbee45175
diff --git a/dbus/dbuspassiveredundancy.cpp b/dbus/dbuspassiveredundancy.cpp
index 11533f2..2ca8fde 100644
--- a/dbus/dbuspassiveredundancy.cpp
+++ b/dbus/dbuspassiveredundancy.cpp
@@ -24,6 +24,9 @@
 #include <unordered_map>
 #include <variant>
 
+namespace pid_control
+{
+
 namespace properties
 {
 
@@ -175,4 +178,6 @@
 const std::set<std::string>& DbusPassiveRedundancy::getFailed()
 {
     return failed;
-}
\ No newline at end of file
+}
+
+} // namespace pid_control