dmaengine: ioat: remove unused ‘ioat_dma’

In ioat_tx_submit_unlock(), variable ‘ioat_dma’ is initialized but never
used, which leads to warning with W=1

drivers/dma/ioat/dma.c: In function ‘ioat_alloc_ring_ent’:
drivers/dma/ioat/dma.c:341:25: warning: variable ‘ioat_dma’ set but not used [-Wunused-but-set-variable]
struct ioatdma_device *ioat_dma;

So remove it.

Cc: Dave Jiang <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/ioat/dma.c

···
 {
 	struct ioat_dma_descriptor *hw;
 	struct ioat_ring_ent *desc;
-	struct ioatdma_device *ioat_dma;
 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
 	int chunk;
 	dma_addr_t phys;
 	u8 *pos;
 	off_t offs;
-
-	ioat_dma = to_ioatdma_device(chan->device);
 
 	chunk = idx / IOAT_DESCS_PER_2M;
 	idx &= (IOAT_DESCS_PER_2M - 1);