Revert "UseListOrder: Order GlobalValue uses after initializers"

This reverts commits r214242 and r214243 while I investigate buildbot
failures [1][2][3].  I can't reproduce these failures locally, so if
anyone can see what I've done wrong, I'd appreciate a note.

[1]: http://lab.llvm.org:8011/builders/llvm-hexagon-elf/builds/9840
[2]: http://lab.llvm.org:8011/builders/clang-hexagon-elf/builds/14981
[3]: http://bb.pgr.jp/builders/cmake-llvm-x86_64-linux/builds/15191