davinci_cpdma: don't cast dma_addr_t to pointer

dma_addr_t may be 64-bit wide on 32-bit architectures, so it is not
valid to cast between it and a pointer:

drivers/net/ethernet/ti/davinci_cpdma.c: In function 'cpdma_chan_submit_si':
drivers/net/ethernet/ti/davinci_cpdma.c:1047:12: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
drivers/net/ethernet/ti/davinci_cpdma.c: In function 'cpdma_chan_idle_submit_mapped':
drivers/net/ethernet/ti/davinci_cpdma.c:1114:12: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
drivers/net/ethernet/ti/davinci_cpdma.c: In function 'cpdma_chan_submit_mapped':
drivers/net/ethernet/ti/davinci_cpdma.c:1164:12: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]

Solve this by using two separate members in 'struct submit_info'.
Since this avoids the use of the 'flag' member, the structure does
not even grow in typical configurations.

Fixes: 6670acac

 ("net: ethernet: ti: davinci_cpdma: add dma mapped submit")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>