Change the implemented interfaces list on PassInfo from a std::vector to a manually...

Change the implemented interfaces list on PassInfo from a std::vector to a manually implemented
linked list.  This is a little slower and involves more malloc'ing, but these lists are
typically short, and it allows PassInfo to be entirely constant initializable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108755 91177308-0d34-0410-b5e6-96231b3b80d8