[Mingw-cross-env-list] libiberty.a has gone?

[Nikos Chantziaras]

Using the current hg sources, gcc does not install 
"usr/i686-pc-mingw32/lib/libiberty.a" anymore.  (It's needed for stuff 
like vasprintf() and other functions that mingw lacks.)

The 2.21 release which came with GCC 4.6.0 still installs it.  Any way I 
can convince GCC 4.6.3 (current hg comes with that) to install libiberty.a?

(As a workaround, I simply copied the libiberty.a from GCC 4.6.0 and it 
seems to work.  Having a proper install is preferable though.)