Use physical LED actions from generated code

Today's code returned a hardcoded string for physical LED action
and this patch uses the generated string for the passed in action enum

Fixes openbmc/phosphor-led-manager#2

Change-Id: I960e2d4346966caee526e1a0e8713e18d34b428a
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
diff --git a/manager.hpp b/manager.hpp
index 8dbbcd6..4adb229 100644
--- a/manager.hpp
+++ b/manager.hpp
@@ -97,7 +97,7 @@
          *
          *  @return string equivalent of the passed in enumeration
          */
-        static const char* const getPhysicalAction(Layout::Action action);
+        static std::string getPhysicalAction(Layout::Action action);
 
         /** @brief Chooses appropriate action to be triggered on physical LED
          *  and calls into function that applies the actual action.