dmaengine: timb_dma: fix the spare warinings

Sparse warns:

drivers/dma/timb_dma.c:168:17: warning: mixing different enum types
drivers/dma/timb_dma.c:168:17:     int enum dma_transfer_direction versus
drivers/dma/timb_dma.c:168:17:     int enum dma_data_direction
drivers/dma/timb_dma.c:172:32: warning: mixing different enum types
drivers/dma/timb_dma.c:172:32:     int enum dma_transfer_direction versus
drivers/dma/timb_dma.c:172:32:     int enum dma_data_direction

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>