Cordio: Add SecurityManager singleton

features/FEATURE_BLE/targets/TARGET_CORDIO/CordioPalSecurityManager.h

@@ -266,6 +266,9 @@ public:
     virtual ble_error_t send_keypress_notification(
         connection_handle_t connection, Keypress_t keypress
     );
+
+    // singleton of the ARM Cordio Security Manager
+    static CordioSecurityManager& get_security_manager();
 };
 
 } // cordio

features/FEATURE_BLE/targets/TARGET_CORDIO/source/CordioPalSecurityManager.cpp

@@ -307,6 +307,12 @@ ble_error_t CordioSecurityManager::send_keypress_notification(
     return BLE_ERROR_NOT_IMPLEMENTED;
 }
 
+CordioSecurityManager& CordioSecurityManager::get_security_manager()
+{
+    static CordioSecurityManager _security_manager;
+    return _security_manager;
+}
+
 } // cordio
 } // vendor
 } // pal