config: allow led priority to be Off

This makes the configuration more flexible and eliminates the edge case.

I don't see why this should not be possible.

Change-Id: I28e33535539b3214e18d7816314656df5d3c370e
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>
diff --git a/manager/json-parser.hpp b/manager/json-parser.hpp
index e17568b..8f2832b 100644
--- a/manager/json-parser.hpp
+++ b/manager/json-parser.hpp
@@ -18,7 +18,6 @@
 using Json = nlohmann::json;
 
 // Priority for a particular LED needs to stay SAME across all groups
-// phosphor::led::Layout::Action can only be one of `Blink` and `On`
 using PriorityMap =
     std::unordered_map<std::string,
                        std::optional<phosphor::led::Layout::Action>>;
@@ -56,14 +55,25 @@
  *
  *  @param[in] action - action string
  *
- *  @return Action - action enum (On/Blink)
+ *  @return Action - action enum (On/Off/Blink)
  */
 phosphor::led::Layout::Action getAction(const std::string& action)
 {
-    assert(action == "On" || action == "Blink");
+    if (action == "On")
+    {
+        return phosphor::led::Layout::Action::On;
+    }
+    if (action == "Off")
+    {
+        return phosphor::led::Layout::Action::Off;
+    }
+    if (action == "Blink")
+    {
+        return phosphor::led::Layout::Action::Blink;
+    }
 
-    return action == "Blink" ? phosphor::led::Layout::Action::Blink
-                             : phosphor::led::Layout::Action::On;
+    assert(false);
+    return phosphor::led::Layout::Action::Blink;
 }
 
 static std::string priorityToString(