Glibc. This is useful when building GCC.
* gcc-wrapper: the dynamic linker has a different name on x86_64 and
powerpc.
* gcc-wrapper: "glibc" -> "libc", because someday we might support
different C libraries.
* gcc: don't do a multilib build (e.g., 32-bit support on x86_64),
don't need it.
* gcc: merge in support for static builds.
* gcc: various simplifications in the compiler/linker flags, hope they
work.
svn path=/nixpkgs/trunk/; revision=6823
