manpage: Missing description of gw_mode sel_class for B.A.T.M.A.N. V
The commit 80b2d47be2c7 ("batman-adv: B.A.T.M.A.N. V - implement GW selection logic") introduced the new bandwidth based threshold for B.A.T.M.A.N. V. But as Martin Weinelt <firstname.lastname@example.org> noticed, this information is not described in the batctl manpage. Instead, it defines only TQ thresholds for B.A.T.M.A.N. IV without mentioning that this information is actually only for IV and not V.