Staging: w35und: remove global struct ieee80211_hw

Remove the my_dev global variable from wbusb.c by passing a pointer to struct
ieee80211_hw around so that packet_came() gets it.

Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>