New 32-bit prebuilt linux toolchain to build SDK

This special 32-bit GCC 4.6 toolchain is used by linux sdk build to
ensure the generated host binaries can run on Ubuntu 8.04 with older
Glibc and libstdc++.  It also comes with sysroot containing libraries
needed by sdk tools, such that compiling sdk tool becomes less dependent
on the pre-installed libraries at host.

This is built by build-hardy-toolchain.sh (also enclosed, slightly
modified from digit@'s) with "--32-bits --bootstrap" on 64-bit
Ubuntu 8.04. (See http://b/issue?id=5957073)  It can run on Ubuntu
8.04 too.

Change-Id: I22d8da7192b6ffc109fddcb8623f4d6e0b7d0822
2408 files changed