ipv6: delete protocol and unregister rtnetlink when cleanup
ipv6: delete protocol and unregister rtnetlink when cleanup

pim6_protocol was added when initiation, but it not deleted.
Similarly, unregister RTNL_FAMILY_IP6MR rtnetlink.

Signed-off-by: Duan Jiong <8328e395f8c1e2c56506478ccd778989e2637711@cn.fujitsu.com>
Reviewed-by: Cong Wang <2b3b59efb30d692c772b2f93c636eba69bba4f54@twopensource.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs