xbps-remove: misc changes to the clean-cache mode.

- If orphans mode is not set, exit directly.
- Simplify the clean-cache code to avoid unnecessary allocs in some cases.

bin/xbps-remove/main.c

@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 2008-2014 Juan Romero Pardines.
+ * Copyright (c) 2008-2015 Juan Romero Pardines.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -269,7 +269,7 @@ main(int argc, char **argv)
 
 	if (clean_cache) {
 		rv = clean_cachedir(&xh);
-		if (rv != 0)
+		if (!orphans || rv)
 			exit(rv);;
 	}