Fix HV/OS parameter validation on non-vm nodes
Fix HV/OS parameter validation on non-vm nodes

Currently, there is at least one LU that does wrong validation of HV
parameters (against all nodes, LUClusterSetParams). It's possible to
fix this case, but I went and modified the base functions to filter
out non-vm_capable nodes so all callers are protected.

Note: the _CheckOSParams function is never called with all nodes list,
so modifying it shouldn't be needed. However, I think it's safe to do
so (and it shouldn't hurt as an instance's node shouldn't ever lack
the vm_capable bit).

Signed-off-by: Iustin Pop <acf83a5274f31a43af6b914614365999469c1a31@google.com>
Reviewed-by: Michael Hanselmann <68b67885ff74281219b4a4be33cc20fd45078d7c@google.com>

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