be2net: remove unused old custom busy-poll fields

The commit fb6113e6 ("be2net: get rid of custom busy poll code")
replaced custom busy-poll code by the generic one but left several
macros and fields in struct be_eq_obj that are currently unused.
Remove this stuff.

Fixes: fb6113e6 ("be2net: get rid of custom busy poll code")
Signed-off-by: Ivan Vecera <cera@cera.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>