Pass -f to rm to ignore empty lists

Author: alexcrichton

master/master.cfg

@@ -1185,7 +1185,7 @@ def distsnap_buildfactory(platform, channel_label):
         for host in all_platform_hosts(platform):
             # `find`, not `ls`, because we need the full path to what we'll remove
             clean_cmd = "find " + local_dist_platform_dir + \
-                            "/*.gz | grep " + host + " | xargs rm"
+                            "/*.gz | grep " + host + " | xargs rm -f"
             f.addStep(MasterShellCommand(name="remove " + host + " artifacts",
                                          command=["sh", "-c", clean_cmd]))