dt-bindings: dma: ti: Update maintainer and author information

My employment with TI is coming to an end, add the copyright and author comments
as they due and change the maintainer mail address.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20201215131348.11282-3-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>