dmaengine: imx-sdma: Fix memory leak

The current descriptor is not on any list of the virtual DMA channel.
Once sdma_terminate_all() is called when a descriptor is currently
in flight then this one is forgotten to be freed. We have to call
vchan_terminate_vdesc() on this descriptor to re-add it to the lists.
Now that we also free the currently running descriptor we can (and
actually have to) remove the current descriptor from its list also
for the cyclic case.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Robin Gong <yibin.gong@nxp.com>
Tested-by: Robin Gong <yibin.gong@nxp.com>
Link: https://lore.kernel.org/r/20191216105328.15198-10-s.hauer@pengutronix.de


Signed-off-by: Vinod Koul <vkoul@kernel.org>