Change meaning of the --max-cpu option
Change meaning of the --max-cpu option

Instead of always overriding, we should update the nodes's maxcpu
setting only when the option is specified. Otherwise this will be read
from the cluster or from the Ganeti constant for non-live backends.

Signed-off-by: Iustin Pop <acf83a5274f31a43af6b914614365999469c1a31@google.com>
Reviewed-by: René Nussbaumer <bc755ac45a0e799d1d490cba76febc56d80cc5fc@google.com>

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