net: fix network drivers ndo_start_xmit() return values (part 3)

Fix up wireless drivers that return an errno value to qdisc_restart(), causing
qdisc_restart() to print a warning an requeue/retransmit the skb.

- airo: transmission not implemented for chip, intention is to free and abort
- ipw2200: transmission not implemented for promiscous mode, intention is to
           drop
- prism54: intention is to drop
- wl3501_cs: intention appears to be to drop
- zd1201: error counter indicates intention is to drop

All drivers compile tested.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>