team: cleanup netpoll clode

This started out with fixing a sparse warning, then I realized that
the wrapper function team_netpoll_info could just be collapsed away
by rolling it into the enable code.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>