libs: update to nfs4j-0.6.2

Changelog for nfs4j-0.6.1..nfs4j-0.6.2
    * [2f24baa] nfsv3: fix creation of symbolic link

Acked-by: Albert Rossi
Target: master, 2.7
Require-book: no
Require-notes: no
(cherry picked from commit 1142ec37e8e8eede1ecff49d62357498871ed7de)
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>