blackfin: dma: current count mmr is read only
blackfin: dma: current count mmr is read only

Signed-off-by: Sonic Zhang <c93d368f28096020dd845c4879a931e9d13ab23f@analog.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs