dmaengine: hsu: move memory allocation to GFP_NOWAIT

The GFP_ATOMIC is too strict, and DMAEngine documentation make an advice to use
GFP_NOWAIT. This patch does the conversion.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>