LockSet: add missing check code
LockSet: add missing check code

This check that no operation had been performed before release() was missing in
the test code. Adding it.

Reviewed-by: imsnah



apyrgio/snf-ganeti,mbakke/ganeti,grnet/snf-ganeti,leshchevds/ganeti,apyrgio/snf-ganeti,andir/ganeti,andir/ganeti,ganeti-github-testing/ganeti-test-1,grnet/snf-ganeti,mbakke/ganeti,ganeti/ganeti,mbakke/ganeti,leshchevds/ganeti,dimara/ganeti,bitemyapp/ganeti,yiannist/ganeti,bitemyapp/ganeti,apyrgio/ganeti,yiannist/ganeti,ganeti-github-testing/ganeti-test-1,ganeti/ganeti,onponomarev/ganeti,andir/ganeti,leshchevds/ganeti,onponomarev/ganeti,apyrgio/ganeti,dimara/ganeti,ganeti/ganeti,yiannist/ganeti