vl.c: Abort on unknown -numa option type

Abort in case an invalid -numa option is provided, instead of silently
ignoring it.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

vl.c

@@ -1293,6 +1293,9 @@ static void numa_add(const char *optarg)
             bitmap_set(node_cpumask[nodenr], value, endvalue-value+1);
         }
         nb_numa_nodes++;
+    } else {
+        fprintf(stderr, "Invalid -numa option: %s\n", option);
+        exit(1);
     }
 }