staging: brcm80211: remove static function prototypes from main.c

Function prototypes for static functions are not strictly needed and
considered unwanted by linux community. This patch reorders the
functions in brcmsmac/main.c and gets rid of the prototypes.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>