Now that we have the completed cookie in the dma_chan structure, we
can consolidate the tx_status functions by providing a function to set
the txstate structure and returning the DMA status.  We also provide
a separate helper to set the residue for cookies which are still in
progress.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NJassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@linux.intel.com>