mwifiex: add basic 11h support for station

This patch adds code to parse requested AP's 11h capabilities
and add 11h information in association request.

Also, deauth is sent to the AP after receiving channel switch
announcement event from firmware. This happens when AP advertises
WLAN_EID_CHANNEL_SWITCH IE in it's beacon.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Paul Stewart <pstew@chromium.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>