dmaengine: pl330: Remove unused flags

txd.flags is unused and need not be updated.

Signed-off-by: Harini Katakam <harini.katakam@amd.com>
Link: https://lore.kernel.org/r/20220802102232.17653-1-harini.katakam@amd.com


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