Revert "dmaengine: imx-sdma: Use GFP_NOWAIT for dma allocations"

This reverts commit c1199875, as this depends on another commit
that is going to be reverted.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>