[POWERPC] 83xx: Enable DMA engine on the MPC8377 MDS board.

Signed-off-by: Zhang Wei <wei.zhang@freescale.com>
Cc: "Nelson, Shannon" <shannon.nelson@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>