Fix dumb mistake

Author: brson

master/master.cfg

@@ -1428,7 +1428,7 @@ def finish_dist(f, local_dist_dir, dist_subdirs, s3_addy, remote_dist_dir, compo
     # package is produced by all builders and if we don't drop the dupes now
     # then the subsequent 'cp' command to consolidate them will fail.
     non_linux_dist_subdirs = list(dist_subdirs)
-    non_linux_dist_subdirs = non_linux_dist_subdirs.remove("linux")
+    non_linux_dist_subdirs.remove("linux")
     non_linux_dist_dirs = [(local_dist_dir + "/" + p) for p in non_linux_dist_subdirs]
     rm_dupes_cmd = "find " + " ".join(non_linux_dist_dirs) + " -name rust-src-" + channel + ".tar.gz | xargs rm -f"
     f.addStep(MasterShellCommand(name="removing duplicate source packages",