cfg80211: fix possible memory leak in cfg80211_iter_combinations()

'limits' is malloced in cfg80211_iter_combinations() and should be freed
before leaving from the error handling cases, otherwise it will cause
memory leak.

Fixes: 0c317a02ca98 ("cfg80211: support virtual interfaces with
different beacon intervals")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git


Git-commit: 320c975f180b19296f0fd6c5bf2144e633aaba5e
CRs-fixed: 1025311
Change-Id: I3fd1ac7cc97a6161642bc5f00ca8b4edc4daa92b
Signed-off-by: Purushottam Kushwaha <pkushwah@codeaurora.org>
Signed-off-by: Vidyullatha Kanchanapally <vidyullatha@codeaurora.org>