selinux: update netlink socket classes

Update the set of SELinux netlink socket class definitions to match
the set of netlink protocols implemented by the kernel.  The
ip_queue implementation for the NETLINK_FIREWALL and NETLINK_IP6_FW protocols
was removed in d16cf20e, so we can remove
the corresponding class definitions as this is dead code.  Add new
classes for NETLINK_ISCSI, NETLINK_FIB_LOOKUP, NETLINK_CONNECTOR,
NETLINK_NETFILTER, NETLINK_GENERIC, NETLINK_SCSITRANSPORT, NETLINK_RDMA,
and NETLINK_CRYPTO so that we can distinguish among sockets created
for each of these protocols.  This change does not define the finer-grained
nlsmsg_read/write permissions or map specific nlmsg_type values to those
permissions in the SELinux nlmsgtab; if finer-grained control of these
sockets is desired/required, that can be added as a follow-on change.
We do not define a SELinux class for NETLINK_ECRYPTFS as the implementation
was removed in 624ae528.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <pmoore@redhat.com>