[trusty] mac80211: don't validate unchanged AP bandwidth while tracking

[AceLan Kao]

BugLink: https://bugs.launchpad.net/bugs/1294558

We need a commit which has been in v3.14-rc6 to fix a 802.11ac
connection problem.
I've verified this commit fixes the issue on a Intel 7260 wifi chip.

commit 963a1852fbac4f75a2d938fa2e734ef1e6d4c044
Author: Johannes Berg <johannes.berg at intel.com>
Date:   Fri Feb 21 20:34:34 2014 +0100

    mac80211: don't validate unchanged AP bandwidth while tracking

    The MLME code in mac80211 must track whether or not the AP changed
    bandwidth, but if there's no change while tracking it shouldn't do
    anything, otherwise regulatory updates can make it impossible to
    connect to certain APs if the regulatory database doesn't match the
    information from the AP. See the precise scenario described in the
    code.

    This still leaves some possible problems with CSA or if the AP
    actually changed bandwidth, but those cases are less common and
    won't completely prevent using it.

    This fixes https://bugzilla.kernel.org/show_bug.cgi?id=70881

    Cc: stable at vger.kernel.org
    Reported-and-tested-by: Nate Carlson <kernel at natecarlson.com>
    Signed-off-by: Johannes Berg <johannes.berg at intel.com>