dmaengine: hsu: Fix memory leak when stopping a running transfer

The vd->node is removed from the lists when the transfer started so the
vchan_get_all_descriptors() will not find it. This results memory leak.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
[andy: fix the typo to prevent a compilation error]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>