mmc: atmel-mci: restore dma on AVR32

Commit ecb89f2f5f3e7 ("mmc: atmel-mci: remove compat for non DT board
when requesting dma chan") broke dma on AVR32 and any other boards not
using DT.  This restores a fallback mechanism for such cases.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/include/linux/atmel-mci.h b/include/linux/atmel-mci.h
index 9177947..e753062 100644
--- a/include/linux/atmel-mci.h
+++ b/include/linux/atmel-mci.h
@@ -2,6 +2,7 @@
 #define __LINUX_ATMEL_MCI_H
 
 #include <linux/types.h>
+#include <linux/dmaengine.h>
 
 #define ATMCI_MAX_NR_SLOTS	2
 
@@ -37,6 +38,7 @@
  */
 struct mci_platform_data {
 	struct mci_dma_data	*dma_slave;
+	dma_filter_fn		dma_filter;
 	struct mci_slot_pdata	slot[ATMCI_MAX_NR_SLOTS];
 };