patch applied (testsuite): don't reset MAKEFLAGS in recursive make in 'make fast'

[Simon Marlow]

Tue Jul  3 05:34:26 PDT 2007  Simon Marlow <simonmar at microsoft.com>
  * don't reset MAKEFLAGS in recursive make in 'make fast'
  It breaks some tests on Windows, because the stage=2 setting is lost
  in the recursive call.  I don't understand why these variables are
  passed in MAKEFLAGS on Windows (cygwin) but not on Unix, something to
  do with environment variables presumably.

    M ./mk/test.mk -1 +1