fix calculation of loader_start_time

TTS/tts/trainer_tts.py

@@ -476,8 +476,8 @@ class TrainerTTS(TrainerAbstract):
         else:
             batch_num_steps = int(len(self.train_loader.dataset) / self.config.batch_size)
         self.c_logger.print_train_start()
-        loader_start_time = time.time()
         for cur_step, batch in enumerate(self.train_loader):
+            loader_start_time = time.time()
             _, _ = self.train_step(batch, batch_num_steps, cur_step, loader_start_time)
         epoch_time = time.time() - epoch_start_time
         # Plot self.epochs_done Stats