mtd: lpc32xx_mlc: Make driver independent of AMBA DMA engine driver

This patch makes the MLC NAND driver independent of the single AMBA DMA engine
driver by using the platform data provided dma_filter callback.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>