mac80211: allow same PN for AMSDU sub-frames

mac80211: allow same PN for AMSDU sub-frames

commit f631a77ba920f7153a1094d09cd8f2ebbffd0328 upstream.

Some hardware (iwlwifi an example) de-aggregate AMSDUs and copy the IV
as is to the generated MPDUs, so the same PN appears in multiple
packets without being a replay attack.  Allow driver to explicitly
indicate that a frame is allowed to have the same PN as the previous
frame.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: Sriram R <srirrama@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>