[add] dma_mask field to struct udmabuf_driver_data, and dma_set_mask() to udmabuf_driver_create(), so that it can be dma_alloc_coherent() with other than the ARM architecture
[add] dma_mask field to struct udmabuf_driver_data, and dma_set_mask() to udmabuf_driver_create(), so that it can be dma_alloc_coherent() with other than the ARM architecture

ikwzm/udmabuf