software_spec: no _or_later in bottle filenames.

It's more useful to be able to "bless" an existing bottle to be used on
later OSs (e.g. where it cannot yet be built) than it is to have to
create a new, identical bottle just to have a different filename.

Library/Homebrew/extend/os/mac/utils/bottles.rb

@@ -38,7 +38,6 @@ module Utils
 
       # Allows a bottle tag to specify a specific OS or later,
       # so the same bottle can target multiple OSs.
-      # Not used in core, used in taps.
       def find_or_later_tag(tag)
         begin
           tag_version = MacOS::Version.from_symbol(tag)

Library/Homebrew/software_spec.rb

@@ -221,7 +221,7 @@ class Bottle
     def initialize(name, version, tag, rebuild)
       @name = name
       @version = version
-      @tag = tag
+      @tag = tag.to_s.gsub(/_or_later$/, "")
       @rebuild = rebuild
     end