Linux SMB3 client quality improvements

Linux SMB3 client quality improvements

[Steve French]

Have been running a large set of xfstests against various server types
and comparing where we were earlier this year with now - and see big
improvements.

Here are some examples from cifs.ko to Samba server e.g. - comparing
the 6.3 kernel from earlier this year to the current 6.6 kernel.    10
additional tests pass:

No longer skipped: generic/051, 068, 390, 491
No longer failed: generic/049, 069, 434, 474, 505, 524

But ... we do have to check carefully, it looks like we do have two
intermittent failures (mount/umount busy regressions due to deferred
close) that were introduced after 6.3:
New failures: 046, 048

Thank you Paulo, Shyam, Bharath and others for helping work through
some of these.  From my investigations it looks like we should be able
to get 20 to 30 additional test groups (from xfstests, the standard
filesystem functional test suite) passing with a series of minor fixes
and features.

Good progress ...
-- 
Thanks,

Steve