dmaengine: xgene-dma: Fix the resource map to handle overlapping

There is an overlap in dma ring cmd csr region due to sharing of ethernet
ring cmd csr region. This patch fix the resource overlapping by mapping
the entire dma ring cmd csr region.

Signed-off-by: Rameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>