staging: wilc1000: refactor p2p action frames handling API's

Refactor handling of P2P specific action frames. Make use of 'struct' to
handle the P2P frames instead of manipulating using 'buf' pointer.
Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Link: https://lore.kernel.org/r/20200212154503.8835-1-ajay.kathat@microchip.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>