crypto: atmel-aes - reduce latency of DMA completion

atmel_aes_dma_callback() now directly calls the 'resume' callback instead
of scheduling the done task, which in turn only calls the very same
'resume' callback.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/atmel-aes.c

@@ -337,8 +337,8 @@ static void atmel_aes_dma_callback(void *data)
 {
 	struct atmel_aes_dev *dd = data;
 
-	/* dma_lch_out - completed */
-	tasklet_schedule(&dd->done_task);
+	dd->is_async = true;
+	(void)dd->resume(dd);
 }
 
 static int atmel_aes_crypt_dma(struct atmel_aes_dev *dd,