SNDPOutFlag to DAG nodes. These properties do not belong to target specific
instructions.
* Added DAG node property SNDPOptInFlag. It's same as SNDPInFlag except it's
optional. Used by ret / call, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25154 91177308-0d34-0410-b5e6-96231b3b80d8