dmaengine: ti: k3-udma: Fix pktdma rchan TPL level setup

Instead of initializing the rchan_tpl the initial commit re-initialized
the tchan_tpl.

Fixes: d2abc982

 ("dmaengine: ti: k3-udma: Initial support for K3 PKTDMA")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20201216154833.20821-1-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>