[PATCH] smb3: Incorrect size for netname negotiate context

commit df58fae72428b "smb3: Incorrect size for netname negotiate context" (patch was added in 5.4) turns out to be more important than we realized (fixing a feature added in 5.3 by commit 96d3cca1241d6 which sends the "netname context" during protocol negotiations).

commit df58fae72428b should be cc:stable for 5.3