eglibc-testing: Clean the test before running them
We make sure that we use final cross gcc to run the tests
since they require proper functioning libstdc++ and libssp
which are not staged in tcbootstrap sysroot
We cleanup the tests before we run them so they all
get run in case any of them were built and/or run during compilation
Make the script executable
Add more documentation to diagnose setup problems
Signed-off-by: Khem Raj <raj.khem@gmail.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
