Change mutex lock model to avoid dead lock and ensure locks are always released.

Additional cosmetic fixes:
 move 'name' as protected
 remove unnecessary local var
 Fix debug log

src/device/device_default.cpp

@@ -81,6 +81,17 @@ namespace hw {
             dfns();
         }
 
+
+        /* ======================================================================= */
+        /*  LOCKER                                                                 */
+        /* ======================================================================= */ 
+    
+        void device_default::lock() { }
+
+        bool device_default::try_lock() { return true; }
+
+        void device_default::unlock() { }
+
         /* ======================================================================= */
         /*                             WALLET & ADDRESS                            */
         /* ======================================================================= */