mwifiex: support to send deauth for P2P client

During P2P handshake, P2P client needs to send deauth after EAPOL
FAILURE to GO. We need add bss mode for P2P client when handle deauth
request.

Without this change, deauth can not be sent out from P2P client side.

Signed-off-by: Stone Piao <piaoyun@marvell.com>
Signed-off-by: Avinash Patil <patila@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>