cleanup: fix for formula/cask name collision

When a formula and cask share the same name, a download can be
incorrectly considered stale. Only check for if a download is a stale
formula or stale cask, but not both.

Library/Homebrew/cleanup.rb

@@ -59,7 +59,11 @@ module CleanupRefinement
     def stale?(scrub = false)
       return false unless resolved_path.file?
 
-      stale_formula?(scrub) || stale_cask?(scrub)
+      if dirname.basename.to_s == "Cask"
+        stale_cask?(scrub)
+      else
+        stale_formula?(scrub)
+      end
     end
 
     private
@@ -113,8 +117,6 @@ module CleanupRefinement
     def stale_cask?(scrub)
       return false unless name = basename.to_s[/\A(.*?)\-\-/, 1]
 
-      return if dirname.basename.to_s != "Cask"
-
       cask = begin
         Cask::CaskLoader.load(name)
       rescue Cask::CaskUnavailableError