patch applied (ghc-6.8/packages/base): protect console handler against concurrent access (#1922)

[Ian Lynagh]

Tue Dec  4 07:39:40 PST 2007  Simon Marlow <simonmar at microsoft.com>
  * protect console handler against concurrent access (#1922)

    M ./GHC/Conc.lhs -15 +45
    M ./GHC/ConsoleHandler.hs -19 +29