macsec: fix netlink attribute for key id

In my last commit I replaced MACSEC_SA_ATTR_KEYID by
MACSEC_SA_ATTR_KEY.

Fixes: 8acca6ac

 ("macsec: key identifier is 128 bits, not 64")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>