dmaengine: dw-edma: Fix typo in comments offset

Fix typo in comments offset related to padding bytes.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Link: https://lore.kernel.org/r/d7c7e56a83a13a62438a6c1a23863015a3760581.1597327654.git.gustavo.pimentel@synopsys.com


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