gcc libraries packaged in lrte runtime

[dionescu]

The libraries for the GCC used to build glibc are packaged under /usr/lrte. This can create all sorts of havoc, especially when the version of the crosstool GCC under /usr/crosstool is different from that of the GCC used to build glibc.

This is one of the issues I ran into when attempting to update the crosstool to GCC 7.3 and clang 6.0.