tipc: involve namespace infrastructure

Involve namespace infrastructure, make the "tipc_net_id" global
variable aware of per namespace, and rename it to "net_id". In
order that the conversion can be successfully done, an instance
of networking namespace must be passed to relevant functions,
allowing them to access the "net_id" variable of per namespace.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc net/tipc/bcast.c
Simple merge

diff --cc net/tipc/bcast.h
Simple merge

diff --cc net/tipc/bearer.c
Simple merge

diff --cc net/tipc/bearer.h
Simple merge

diff --cc net/tipc/config.c
Simple merge

diff --cc net/tipc/config.h
Simple merge

diff --cc net/tipc/core.c
Simple merge

diff --cc net/tipc/core.h
Simple merge

diff --cc net/tipc/discover.c
Simple merge

diff --cc net/tipc/discover.h
Simple merge

diff --cc net/tipc/link.c
Simple merge

diff --cc net/tipc/msg.c
Simple merge

diff --cc net/tipc/net.c
Simple merge

diff --cc net/tipc/net.h
Simple merge

diff --cc net/tipc/netlink.c
Simple merge