[Bug libstdc++/51701] Remove reference to Henry Suter's RWLock from documentation

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51701

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-12-29 15:31:05 UTC ---
For the record the code can be found at
http://web.archive.org/web/20070810183256/http://suter.home.cern.ch/suter/RWLock.html
but I agree that referring to it from the libstdc++ manual isn't very useful