libxl: set correct credit cpu weight, when no one is specified in the config file

all default values have to be set to 0, but for the credit(2) scheduler
cpu_weight has to be 256 by default.
So if the weight isn't given in the confgfile we use 256 for the credit(2)
scheduler and 0 for sedf

Signed-off-by: Dieter Bloms <dieter@xxxxxxxx>

diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
index c246211..ec2e3af 100644
--- a/tools/libxl/libxl_dom.c
+++ b/tools/libxl/libxl_dom.c
@@ -62,12 +62,18 @@ int libxl__sched_set_params(libxl__gc *gc, uint32_t domid, libxl_sched_params *s
       ret=libxl_sched_sedf_domain_set(ctx, domid, &sedf_info);
       break;
     case LIBXL_SCHEDULER_CREDIT:
-      credit_info.weight = scparams->weight;
+      if (scparams->weight)
+          credit_info.weight = scparams->weight;
+      else
+          credit_info.weight = 256;
       credit_info.cap = scparams->cap;
       ret=libxl_sched_credit_domain_set(ctx, domid, &credit_info);
       break;
     case LIBXL_SCHEDULER_CREDIT2:
-      credit2_info.weight = scparams->weight;
+      if (scparams->weight)
+          credit2_info.weight = scparams->weight;
+      else
+          credit_info.weight = 256;
       ret=libxl_sched_credit2_domain_set(ctx, domid, &credit2_info);
       break;
     default: