staging: brcm80211: cleanup to get rid of 'over 80 character' line

One checkpatch warning was remaining in the brcmsmac driver. The
code has been restructured to get rid of this last checkpatch
warning.

Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>