Revert "[Support] Replace HashString with djbHash."
It looks like some of our tests depend on the ordering of hashed values.
I'm reverting my changes while I try to reproduce and fix this locally.
Failing builds:
lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/18388
lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/6743
lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/15607
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326082
91177308-0d34-0410-b5e6-
96231b3b80d8