mlxsw: spectrum_acl_atcam: Fix wrong comment

The key is encoded, not encrypted.

Fixes: c22291f7 ("mlxsw: spectrum: acl: Implement delta for ERP")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Tested-by: Alexander Zubkov <green@qrator.net>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>