This patch replaces magic values with preprocessor definitions for
the sg_dig_ctrl and sg_dig_status registers.  This is preparatory work
for the next patch.
Signed-off-by: NMatt Carlson <mcarlson@broadcom.com>
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>