control: Declare non-templated handlers as inline

Found this issue while testing the use of the handlers within the
trigger objects created from JSON.

Change-Id: I14dce54bc9b20ae3e1c08f5d4223d28cce5c505c
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
diff --git a/control/handlers.hpp b/control/handlers.hpp
index 1e82b37..7fb7dfc 100644
--- a/control/handlers.hpp
+++ b/control/handlers.hpp
@@ -66,7 +66,7 @@
  * @return Lambda function
  *     A lambda function to set/update the service name owner state
  */
-auto setService(Group&& group)
+inline auto setService(Group&& group)
 {
     return [group = std::move(group)](auto& zone, auto& name, bool hasOwner) {
         // Update service name owner state list of a group
@@ -85,7 +85,7 @@
  * @return Lambda function
  *     A lambda function to remove the interface
  */
-auto removeInterface(const char* path, const char* interface)
+inline auto removeInterface(const char* path, const char* interface)
 {
     return [=](auto& zone) { zone.removeObjectInterface(path, interface); };
 }