Copy the full TailCallKind in CallInst::clone_impl

Split from the musttail inliner change.  This will be covered by an opt
test when the inliner change lands.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208126 91177308-0d34-0410-b5e6-96231b3b80d8