Remove usages of deprecated std::unary_function and std::binary_function.

These are removed in C++17. We still have some users of
unary_function::argument_type, so just spell that typedef out. No
functionality change intended.

Note that many of the argument types are actually wrong :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313287 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed