mmc: bfin_sdh: fix dma_desc_array build error

Descriptor array structure has been moved into blackfin dma.h head file.
This patch fix below error:

drivers/mmc/host/bfin_sdh.c:52:8: error: redefinition of 'struct
dma_desc_array'
make[4]: *** [drivers/mmc/host/bfin_sdh.o] Error 1
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NBob Liu <lliubbo@gmail.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

drivers/mmc/host/bfin_sdh.c

@@ -49,13 +49,6 @@
 #define bfin_write_SDH_CFG		bfin_write_RSI_CFG
 #endif
 
-struct dma_desc_array {
-	unsigned long	start_addr;
-	unsigned short	cfg;
-	unsigned short	x_count;
-	short		x_modify;
-} __packed;
-
 struct sdh_host {
 	struct mmc_host		*mmc;
 	spinlock_t		lock;