Make htools tolerate missing "spfree" on luxi
Make htools tolerate missing "spfree" on luxi

If a cluster allows sharedfile as only disk template, the
amount of free spindles might not be available. This is
perfectly normal, hence the luxi backend of htools should
handle this case gracefully and just report 0 available spindles.

Signed-off-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>
Reviewed-by: Hrvoje Ribicic <be5828fca31f89218048bec4189e30a581aa65da@google.com>

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