[patch libstdc++]: Add some missing errno-constants for mingw-targets

[Robert Dewar]

On 8/29/2011 4:50 PM, Paolo Carlini wrote:
> .. also, you forgot to add 2011 to the Copyright years.
>
> Paolo.

In the GNAT development environment we have an SVN style
checking filter, and this is one of the things it checks
for so we prevent any checkin missing the current year in
the copyright notice.