New libstdc++ on AIX

[David Edelsohn]

	This patch:

2005-05-27  Benjamin Kosnik  <bkoz@redhat.com>

        PR libstdc++/21674
        * include/bits/c++config: Remove extern template use when in debug
        mode, disable for non-weak systems.

appears to be the cause of many new compilation errors on AIX.  The excess
errors look like:

libstdc++-v3/include/powerpc-ibm-aix5.2.0.0/bits/c++config.h:61:4:
warning: #warning debug mode disabled due to lack of weak symbol support
libstdc++-v3/include/bitset: In static member function 'static size_t
_GLIBCXX_STD::_Base_bitset<_Nw>::_S_whichword(size_t)':
libstdc++-v3/include/bitset:95: error: 'numeric_limits' was not declared
in this scope
libstdc++-v3/include/bitset:95: error: expected primary-expression before
'unsigned'
libstdc++-v3/include/bitset:95: error: expected ';' before
'unsigned'

With similar warning and following parse errors for the other 12 or so new
failures.

etc.

David