Description: tipc: fix NULL deref in tipc_link_xmit()
References:
 https://bugzilla.redhat.com/show_bug.cgi?id=2178212
Notes:
Bugs:
upstream: released (5.11-rc4) [b77413446408fdd256599daf00d5be72b5f3e7c6]
6.1-upstream-stable: N/A "Fixed before branching point"
5.10-upstream-stable: released (5.10.10) [60b8b4e6310b7dfc551ba68e8639eeaf70a0b2dd]
4.19-upstream-stable: released (4.19.170) [4d1d3dddcb3f26000e66cd0a9b8b16f7c2eb41bb]
sid: released (5.10.12-1)
5.10-bullseye-security: N/A "Fixed before branching point"
4.19-buster-security: released (4.19.171-1)