Export a compat function for older Setup.hs scripts

Makes it possible for alex and happy to work with cabal-1.2 -> 1.6

Distribution/Simple/Setup.hs

@@ -65,6 +65,7 @@ module Distribution.Simple.Setup (
   HaddockFlags(..),  emptyHaddockFlags,  defaultHaddockFlags,  haddockCommand,
   HscolourFlags(..), emptyHscolourFlags, defaultHscolourFlags, hscolourCommand,
   BuildFlags(..),    emptyBuildFlags,    defaultBuildFlags,    buildCommand,
+  buildVerbose,
   CleanFlags(..),    emptyCleanFlags,    defaultCleanFlags,    cleanCommand,
   MakefileFlags(..), emptyMakefileFlags, defaultMakefileFlags, makefileCommand,
   RegisterFlags(..), emptyRegisterFlags, defaultRegisterFlags, registerCommand,
@@ -1153,6 +1154,10 @@ data BuildFlags = BuildFlags {
   }
   deriving Show
 
+{-# DEPRECATED buildVerbose "Use buildVerbosity instead" #-}
+buildVerbose :: BuildFlags -> Verbosity
+buildVerbose = fromFlagOrDefault normal . buildVerbosity
+
 defaultBuildFlags :: BuildFlags
 defaultBuildFlags  = BuildFlags {
     buildProgramPaths = mempty,