During the refactoring for the ksz8_dev_ops from ksz8795.c to
ksz_common.c, the ksz8_r_mib_cnt has been missed. So this patch adds the
missing one.
Fixes: 6ec23aaaac43 ("net: dsa: microchip: move ksz_dev_ops to ksz_common.c")
Signed-off-by: Arun Ramadoss <arun.ramadoss@xxxxxxxxxxxxx>