tools/xl: fix output of xl vcpu-pin dry run with smt=0

Fix another smt=0 fallout: xl -N vcpu-pin prints only parts of the
affinities as it is using the number of online cpus instead of the
maximum cpu number.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>

tools/xl/xl_vcpu.c

@@ -255,9 +255,9 @@ int main_vcpupin(int argc, char **argv)
         goto out;
 
     if (dryrun_only) {
-        nb_cpu = libxl_get_online_cpus(ctx);
+        nb_cpu = libxl_get_max_cpus(ctx);
         if (nb_cpu < 0) {
-            fprintf(stderr, "libxl_get_online_cpus failed.\n");
+            fprintf(stderr, "libxl_get_max_cpus failed.\n");
             goto out;
         }