Use binutils 2.39 branch in build-many-glibcs.py

This patch makes build-many-glibcs.py use binutils 2.39 branch.

Tested with build-many-glibcs.py (compilers and glibcs builds).  Note:
binutils 2.39 shows the same failures for i686-linux-gnu-no-pie,
x86_64-linux-gnu-no-pie and x86_64-linux-gnu-x32-no-pie building the
glibc testsuite as binutils mainline does.