Fix a wrong comparison in _RecursiveAssembleBD
Fix a wrong comparison in _RecursiveAssembleBD

We want to prevent sending too many 'None' children to a device.
However, the test as it is today is wrong, as we want to test the
situation after adding a new child, and not before. This patch fixes
this by testing greater-or-equal instead of just greater.

Reviewed-by: imsnah


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