wil6210: stop_ap to leave interface closed

cfg80211_ops.stop_ap supposed to have interface carried turned off as
post condition. Fulfill this requirement.

Change-Id: I90e0f51b15576925c825c78ffe69e2254144872b
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Git-commit: e853c93bd8e2d92c6586ceed15542c21c8766d54
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-testing.git


Signed-off-by: Hamad Kadmany <hkadmany@codeaurora.org>