Refactor and document `Hardware`.

Library/Homebrew/extend/os/linux/hardware/cpu.rb

@@ -11,10 +11,6 @@ module Hardware
         end
       end
 
-      def cpuinfo
-        @cpuinfo ||= File.read("/proc/cpuinfo")
-      end
-
       def family
         return :arm if arm?
         return :ppc if ppc?
@@ -94,6 +90,12 @@ module Hardware
       def sse4?
         flags.include? "sse4_1"
       end
+
+      private
+
+      def cpuinfo
+        @cpuinfo ||= File.read("/proc/cpuinfo")
+      end
     end
   end
 end

Library/Homebrew/hardware.rb

@@ -2,7 +2,9 @@
 
 require "utils/popen"
 
+# Helper module for querying hardware information.
 module Hardware
+  # Helper module for querying CPU information.
   class CPU
     INTEL_32BIT_ARCHS = [:i386].freeze
     INTEL_64BIT_ARCHS = [:x86_64].freeze