staging: vt6655: Replace MACvReadMIBCounter with VNSvInPortD

Replace macro MACvReadMIBCounter with VNSvInPortD and as it
was the only user, it can now be removed.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/e1b7156e2c689cf53c738642fd9b33816ec89f92.1651036713.git.philipp.g.hortmann@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>