mka: Fix resource leak when detecting duplicated SCI

mka: Fix resource leak when detecting duplicated SCI

If a live peer ever changes its Member Identifier (MI), the KaY
correctly detects a "duplicated SCI" but then proceeds to delete the
peer without deleting the peer's resources (i.e., RxSC, RxSAs, TxSAs).

Note that a remote peer's MI will change if and when an
ieee8021XPaePortInitialize is executed on the remote port.

The solution here is to ignore all MKPDUs containing the new MI until
after the peer (that corresponds to the old MI) expires and cleans up
its resources. After the old peer is removed reception of the next MKPDU
containing the new MI will result in the creation of a new peer with the
new MI.

Signed-off-by: Michael Siedzik <msiedzik@extremenetworks.com>