vyos-open-vm-tools: disable sync driver by default to prevent crashing

Update /etc/vmware-tools/tools.conf to include enableSyncDriver = false
in order to disable filesystem freezing by default.  This is a
temporary workaround until the underlying issue can be resolved, but it
at least prevents a total lock up of the VM when it is backed up with
filesystem quiescing enabled on the host.

Bug #583 http://bugzilla.vyos.net/show_bug.cgi?id=583
Bug #413 http://bugzilla.vyos.net/show_bug.cgi?id=413

open-vm-tools/debian/local/tools.conf

@@ -1 +1,4 @@
 bindir = "/usr/bin"
+
+[vmbackup]
+enableSyncDriver = false