staging: brcm80211: replaced typedef struct wl_info_t by struct wl_info.

Part of the code cleanup effort. CodingStyle doc advises to restrict the usage
of typedefs. Also moved several function declarations from .c to .h file
because this typedef replace operation induced checkpatch.pl warnings.

Signed-off-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>