The MS-CIFS spec, section 22.214.171.124.1 states that only a single lock cancel
request can be made per PDU. The Samba4 server handles this correctly, but
then returns an incorrect error code when a locked file is unlocked.
Interestingly, Windows servers do not conform to the spec and allow multiple
lock cancellation requests to be made without error.
This behavior is exercised by the RAW-LOCK-ASYNC smbtorture4 test.
samba4.raw.lock.*.async should be removed from
source4/selftest/knownfail when this bug is fixed.
Reassign file server related bugs up to tridge.