[Bug libstdc++/21131] Mismatch in comments for m4 config macros in libstdc++

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
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      Known to work|                            |3.4.4 4.0.1 4.1.0
   Target Milestone|---                         |3.4.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21131