dmaengine: at_xdmac: GFP_KERNEL for user that can sleep

device_alloc_chan_resources can sleep, use GFP_KERNEL flag.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Link: https://lore.kernel.org/r/20200123140237.125799-9-tudor.ambarus@microchip.com


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