macsec: fix memory leaks around rx_handler (un)registration

macsec: fix memory leaks around rx_handler (un)registration

We leak a struct macsec_rxh_data when we unregister the rx_handler in
macsec_dellink.
We also leak a struct macsec_rxh_data in register_macsec_dev if we fail
to register the rx_handler.

Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 960d5848dbf1245cc3a310109897937207411c0c)

Orabug: 24614549

Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com>
Signed-off-by: Dhaval Giani <dhaval.giani@oracle.com>