dmaengine: initialize tx_list in dma_async_tx_descriptor_init

Centralize this common initialization (and one case where ipu_idmac is
duplicating ->chan initialization).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 49243d1..a41d1ea 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -920,6 +920,7 @@
 {
 	tx->chan = chan;
 	spin_lock_init(&tx->lock);
+	INIT_LIST_HEAD(&tx->tx_list);
 }
 EXPORT_SYMBOL(dma_async_tx_descriptor_init);
 
diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index a97c07e..862fc9c 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -826,7 +826,6 @@
 		dma_async_tx_descriptor_init(&desc->txd, chan);
 		desc->txd.tx_submit = dwc_tx_submit;
 		desc->txd.flags = DMA_CTRL_ACK;
-		INIT_LIST_HEAD(&desc->txd.tx_list);
 		desc->txd.phys = dma_map_single(chan2parent(chan), &desc->lli,
 				sizeof(desc->lli), DMA_TO_DEVICE);
 		dwc_desc_put(dwc, desc);
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 86d6da4..da8a8ed 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -354,7 +354,6 @@
 		dma_async_tx_descriptor_init(&desc_sw->async_tx,
 						&fsl_chan->common);
 		desc_sw->async_tx.tx_submit = fsl_dma_tx_submit;
-		INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
 		desc_sw->async_tx.phys = pdesc;
 	}
 
diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c
index 5905cd3..e4fc33c 100644
--- a/drivers/dma/ioat_dma.c
+++ b/drivers/dma/ioat_dma.c
@@ -693,7 +693,6 @@
 		desc_sw->async_tx.tx_submit = ioat2_tx_submit;
 		break;
 	}
-	INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
 
 	desc_sw->hw = desc;
 	desc_sw->async_tx.phys = phys;
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c
index 16adbe6..2f05226 100644
--- a/drivers/dma/iop-adma.c
+++ b/drivers/dma/iop-adma.c
@@ -498,7 +498,6 @@
 		slot->async_tx.tx_submit = iop_adma_tx_submit;
 		INIT_LIST_HEAD(&slot->chain_node);
 		INIT_LIST_HEAD(&slot->slot_node);
-		INIT_LIST_HEAD(&slot->async_tx.tx_list);
 		hw_desc = (char *) iop_chan->device->dma_desc_pool;
 		slot->async_tx.phys =
 			(dma_addr_t) &hw_desc[idx * IOP_ADMA_SLOT_SIZE];
diff --git a/drivers/dma/ipu/ipu_idmac.c b/drivers/dma/ipu/ipu_idmac.c
index 0a525c4..7ce0e25 100644
--- a/drivers/dma/ipu/ipu_idmac.c
+++ b/drivers/dma/ipu/ipu_idmac.c
@@ -983,8 +983,6 @@
 		memset(txd, 0, sizeof(*txd));
 		dma_async_tx_descriptor_init(txd, &ichan->dma_chan);
 		txd->tx_submit		= idmac_tx_submit;
-		txd->chan		= &ichan->dma_chan;
-		INIT_LIST_HEAD(&txd->tx_list);
 
 		list_add(&desc->list, &ichan->free_list);
 
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index cb7f26f..ddab94f 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -632,7 +632,6 @@
 		slot->async_tx.tx_submit = mv_xor_tx_submit;
 		INIT_LIST_HEAD(&slot->chain_node);
 		INIT_LIST_HEAD(&slot->slot_node);
-		INIT_LIST_HEAD(&slot->async_tx.tx_list);
 		hw_desc = (char *) mv_chan->device->dma_desc_pool;
 		slot->async_tx.phys =
 			(dma_addr_t) &hw_desc[idx * MV_XOR_SLOT_SIZE];