[parrot/parrot] 0a0c35: [win32] fix build with MinGW

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/parrot/parrot
  Commit: 0a0c35749a9f3845a351bc3baa02638ae2220fb4
      https://github.com/parrot/parrot/commit/0a0c35749a9f3845a351bc3baa02638ae2220fb4
  Author: Francois Perrad <francois.perrad at gadz.org>
  Date:   2014-12-07 (Sun, 07 Dec 2014)

  Changed paths:
    M src/platform/win32/env.c

  Log Message:
  -----------
  [win32] fix build with MinGW

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