dw_dmac: use proper casting to print dma_addr_t values

dma_addr_t is sometimes 32 bit and sometimes 64. We normally cast them to
unsigned long long for printk().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.linux@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>