entitymap: move accessor to separate module

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I8c80acb694d067043b77d81dbb9a7ba0057fef56
diff --git a/entity_map_json.hpp b/entity_map_json.hpp
index 11530bf..54884ee 100644
--- a/entity_map_json.hpp
+++ b/entity_map_json.hpp
@@ -9,6 +9,11 @@
 {
 
 /**
+ * @brief Grab a handle to the entity map.
+ */
+const EntityInfoMap& getIpmiEntityRecords();
+
+/**
  * @brief Open the default entity map json file, and if present and valid json,
  * return a built entity map.
  *