Fix gcc_update for libcpp (Was: Re: Mainline bootstrap failure while running aclocal in libcpp)

[Paolo Bonzini]

> Note there might be another problem here (missing commit, wrong
> autoconf/automake) but the patch below is necessary in any case,

It looks like you need gettext development packages installed to rebuild 
many configure scripts (or aclocal.m4's as well when using Automake 
1.8.x).  This is the case at least for gcc and libcpp.

Paolo