staging: wilc1000: refactor wilc_wlan_parse_info_frame() function

Return 'void' from wilc_wlan_parse_info_frame() as same constant value
is returned always. Also removed the 'size' from input parameter as its
not used in the function.

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>